Oedipus at Colonus is not unique among Greek tragedies in using oracles as both structuring elements in the plot and clues to interpretation, but Sophocles makes especially telling use of them in this play, as many scholars have noted. Even so, I believe there is a little more to be said, and I hope the topic is one that may appeal to our honorand, whose observations on the name and nature of Apollo may serve as guidelines for this paper, particularly his characterisation of the god as “the word waiting to be translated into action.” 
What I try to argue is that OC is designed to engage its audience – whether spectators or readers – in an exceptionally intense and demanding process of interpretation, as it follows the stages of Oedipus’ growing understanding of his whole life story. The challenge to make sense of oracular messages, and of their recipients’ reactions, proves to be all the more demanding because the answers it yields are never unambiguous. But perhaps this very elusiveness contributes to the play’s continuing power, and it is worth paying close attention to whatever hints can be traced in the play’s language.
One way to begin is with the rather artificial question “How many oracles?” which can be answered in only the roughest terms, but may at least help to throw light on the dramatic structure of OC. Beyond this, all is subject to interpretation and conjecture: for example, there is no way of being certain what precisely were the questions that might have been asked by the many individuals involved, or what was the exact form of any supposed response. Reports are mediated by different speakers, and the language used to describe oracular messages is itself elusive. Such terms as manteia (at 354, 453-4), manteumata (387, 1425), chrêsteria (604, 1331) and thesphata (453; cf. 969-70, 1472) could have a variety of implications: the exact words of the Delphic priests conveying the response of the Pythia, more or less precise reporting by officials sent to the oracle, or later interpretations by seers.  Oedipus himself is interested in this question of sources: at 412-15 he wants to know where Ismene’s new information comes from, and she reports that it was brought back by official Theban envoys (theôroi) to Apollo’s oracle at Delphi. 
(a) Oracle A
The first mention of an oracle comes at 84-110, in Oedipus’ great prayer to the goddesses of the grove at Colonus, but from the start he has been urgently asking where it is that he and Antigone have arrived, and he reacts with intense excitement when a local inhabitant tells him (39-40) that they have stepped on ground sacred to “the fearsome goddesses, daughters of Earth and Darkness,” one of whose local names is “Eumenides.”  He at once presents himself as a suppliant to these goddesses (43-4), and without any further explanation claims to have identified something he calls “the watchword of my fate” (ξυμφορᾶς ξύνθημ ̓ ἐμῆς 46). A process of deduction has evidently been set in train, and Oedipus now has the confidence to ask for a message to be sent to the king, with the startling news that this blind stranger and suppliant has something important to offer him (70-4).
When the local man has left, and Oedipus makes his prayer to the goddesses, his mysterious claims are explained in his summary of Oracle A: he had been told his end would come when he came to “a seat of revered divinities” (θεῶν | σεμνῶν ἕδραν, 89-90, with no specification of gender, since “gods” and “goddesses” have the same form in the genitive plural). The source of this prophecy was Apollo long ago, who when he “foretold to me those many evils,” meaning the killing of his father and marriage with his mother, also, Oedipus now claims, gave him an indication of what would happen at the very close of his life, including the promise of posthumous power (by implication that of a cult hero, 87-93). The reference to “those many evils” would clearly suggest to audiences familiar with OT the passage in that play when Oedipus reports to Jocasta the Delphic oracle’s response to a question which must have been along the lines of “Who are my parents?” (787-93);  but there Oedipus speaks only of what was foretold about his treatment of his parents and says nothing about later events in his life. Of course we cannot ask “documentary” questions about what was prophesied to Oedipus at Delphi, and in any case Sophocles was at liberty to re-invent the terms of the “original” oracle when he came to compose OC, but it is interesting that what Oedipus reports here is presented as a new gloss on an old oracular response, not as a quite new piece of information. His guess that he has come to the predicted place marks this moment as “zero hour” for the events of this play, and in linking the past with the present in this way Oedipus’ narrative also gives a crucial preview of the shape of action to come.
By their very nature, oracular pronouncements require progressive interpretation over time in the light of previously unforeseeable events: before his wanderings in exile, Oedipus could be imagined to have had a different sense of what might ultimately be in store for him, especially when he was continuing to live at Thebes. The implication of “the watchword of my fate” (ξυμφορᾶς ξύνθημ᾿ ἐμῆς) at 46 is that Oedipus believes he has at last identified who the “revered divinities” are: as phrased, the label could apply to many divine beings, male or female, worshipped in different cults all over Greece, and in his wanderings up to now he has not come across the relevant sacred spot. He has evidently been unaware that in Attica “Semnai Theai” was a variant on the similarly euphemistic title “Eumenides,” but he guesses now that the final phase of his life is imminent, and at 94-5 he refers to the signs that he was forewarned by the oracle to expect: “And he (Apollo) indicated that signs would come: earthquake, thunder or the lightning flash of Zeus,” a clear hint to the audience of what to look out for. At 1456-1515, when the sudden claps of thunder and lightning flashes are interpreted by Oedipus as the promised signs of his coming end (1508-9; 1516-17) the oracle is explicitly recalled. His reference to “Phoebus and me” at 86 suggests a new confidence on his part, and at 101-5 he begs the goddesses to grant him an end to his life, after all he has suffered, “in accordance with the utterances of Apollo,” but he still has to win over the local community and their king, and nothing is yet certain.
Oracle A is glancingly recalled at 287-8 when Oedipus claims, in response to the horrified reaction of the Chorus, that not only – despite appearances – is he ritually acceptable (ἱερὸς εὐσεβής τε), but he has something to offer to the Athenians, hinted at as early as 72-4. Although he says nothing specific about the oracle here, he seems to be relying on his sense that he has at last found the proper way to read it.
(b) Indeterminate further oracles, or commentaries on oracles, between A and B
When Ismene arrives at 324, bringing crucial information about current events at Thebes, Oedipus recalls with gratitude her previous efforts to keep him informed during his wanderings, bringing “all the prophecies that were made about me” (353-6). No more detail is given of these manteia, but mention of them implies a repeated process of consultation on the part of the Thebans, anxious to know what to do about Oedipus in times of conflict between his sons, and not necessarily able to interpret any given oracular responses they have obtained. The reference is perhaps a reminder of the problems of interpretation from the Theban point of view, and it may help to explain why the meaning of Oracle B is so differently understood by the Thebans and Oedipus. But we have no means of telling exactly what were the terms of the questions that the Thebans put to oracles (or prophets).
(c) Oracle B
At 383-4, having told her father of the disastrous quarrel between Eteocles and Polyneices, Ismene hints that despite the frightful news of war between the brothers she has some puzzling information about a possible change in divine attitudes towards Oedipus: “and I cannot understand how the gods will show pity for your ordeals” (τοὺς δὲ σοὺς ὅπηι θεοὶ | πόνους κατοικτιοῦσιν οὐκ ἔχω μαθεῖν). Oedipus’ response expresses surprise, but he is eager to hear what makes her think the gods might be interested in his being “rescued” (σωθῆναι, 386) after all, which in the context might imply being saved from exile, i.e. restored to Thebes (so perhaps his death is not imminent? Or how might this notion fit with his hoped-for reception at Colonus?).
Ismene explains that her thoughts have been prompted by recent prophecies, τοῖς νῦν … μαντεύμασιν (387), as received by the Thebans. This revelation marks a fresh development, since the latest oracle as reported to them evidently says that Oedipus is to have power to help or harm, and his countrymen are going to be eager to seek him out. The phrase “in death and in life” at 390 hints at future hero cult, and at 392 Ismene elaborates: “They say that their (the Thebans’) power is in your hands” (ἐν σοὶ τὰ κείνων φασὶ γίγνεσθαι κράτη).  But crucially they will not receive him into Theban territory or bury him in Theban ground, because he has shed kindred blood; what they plan is to keep him close to the border, where he can be carefully controlled,  and where after his death his tomb can be safeguarded, as any offence done to his tomb (e.g. failure to give it proper observance), will be dangerous, literally “heavy” for the Thebans: κείνοις ὁ τύμβος δυστυχῶν ὁ σὸς βαρύς, 402. No indication is given of where this prohibition of burial comes from (407), but the bare report is enough to convince Oedipus that he has no prospect of being “saved” at Thebes.
The key section of this exchange is 408-11, often misleadingly interpreted by modern scholars: Oedipus rejects the idea of being controlled by the Thebans (408), and Ismene replies that this will be “heavy” for them to bear (ἔσται ποτ ̓ ἆρα τοῦτο Καδμείοις βάρος, recalling the language of 402). Oedipus then asks “What conjuncture of events having manifested itself?” (ποίας φανείσης … συναλλαγῆς;), a rather elaborate, though vague, way of expressing the idea of some significant happening at a particular time and place. Ismene’s reply at 411 sets out both the predicted cause of the Cadmeans’ misery, namely the anger of Oedipus (τῆς σῆς ὑπ ̓ ὀργῆς), and the occasion, “when they stand at your tomb” (σοῖς ὅταν στῶσιν τάφοις). At its most literal this reads like a reference to some occasion when the Thebans will make offerings to Oedipus at his tomb, hoping for protection, but his anger (at their neglect/ unwillingness to allow him back at Thebes?) will cause them to be harmed (by an enemy?). The use of parts of ἵστασθαι, particularly στῆναι, in ritual contexts can easily be paralleled from tragedy,suggesting the importance of standing in the right position for making contact with the dead person or appropriate deities; at 477 Oedipus is instructed to make drink-offerings to the Semnai, standing facing the East (χοὰς χέασθαι στάντα πρὸς πρώτην ἕω); at Ajax 1171, Eurysaces is to “stand near and in supplication take hold of your father” (σταθεὶς πέλας | ἱκέτης ἔφαψαι πατρός.) 
Commentators have tended to ignore this association, preoccupied with the possibility of a reference to a recent event in the history of conflict between Athens and Thebes, and have understood στῶσιν in a military sense as “take their stand.” This reading relies on a rather flimsy combination of evidence: a reference in a scholion on Aelius Aristeides (Huper tôn tettarôn 172) linking an apparition of Oedipus after his burial at Colonus with an Athenian defeat of Thebans in Attica. A passage in Diodorus (13.72.3-73.2) on a cavalry raid by Thebans during the Decelean War, which was fought off by the Athenians, has been seen as referring to the same event,  but we should try to think first about what the Thebans, Ismene and Oedipus can make of the prophecy. At this stage, Oedipus is hearing Ismene’s account of the oracle for the first time, and his more detailed interpretation will come later (cf. the end of section (c), below). For Ismene and the Thebans, who have not heard Oedipus’ prayer to the goddesses of Colonus, there is no means yet of knowing that his tomb might not be close to Theban territory. 
Having heard this significant news, Oedipus first needs to know its source, which with its reference to envoys to the oracle (412-15) sounds as official as one could hope for, and then to find out whether both his sons are aware of it and still do not wish to re-establish him in Thebes. When this is confirmed, he reacts with furious denunciation of his sons and emphatic refusal to give them any support, praying for power to determine the outcome of their conflict (421-54), the first formulation of the violent hatred that culminates in his more explicit curse at 1370-96. His understanding of his situation has also been clarified in two important respects. (a) He sees now that his end will not be at Thebes (where, as he recalls at 437-9, after his initial desperate wish to be exiled he had later been willing to stay, hoping perhaps that the “original oracle” would turn out, as often happened with oracles, to be fulfilled in some unexpected way – and even at this late stage he might conceivably have been attracted by the idea of being welcomed back before the end of his life by his repentant sons and the Theban people). (b) The news from Thebes makes clear that the place he has just reached in Attica will indeed be the place of his death, and his refusal to help either party at Thebes will therefore mean failure for both sides.
The wording of 452-4 is particularly telling in setting out his process of deduction: “This I know, hearing the prophecies reported by (Ismene) and reflecting on oracles pronounced long ago, which Phoebus has fulfilled for me at last” (τοῦτ ̓ ἐγὦιδα, τῆσδέ τε | μαντεῖ ̓ ἀκούων, συννοῶν τε θέσφατα | παλαίφαθ ̓ ἁμοὶ Φοῖβος ἤνυσέν ποτε). It is through putting together what Ismene has told him of new prophecies (385-420), and reflecting on the meaning of his arrival at the grove of the Semnai Theai in relation to what Apollo prophesied to him in the past, that he is able to understand the present situation and know how he must react. His stress on ‘reflecting’, συννοῶν, is important, emphasising the fact that Oedipus does not understand everything in advance, but is actively interpreting the meaning of fresh news in relation to what he knows already. In the text adopted here, the expression “oracles pronounced long ago” (θέσφατα παλαίφαθ᾽) closely echoes the phrasing of a line (ὢ πόποι, ἧ μάλα δή με παλαίφατα θέσφαθ ̓ ἱκάνει) which occurs twice in the Odyssey, each time at a critical moment when the speaker at last recognises the significance of a prophecy given to him long ago. At Odyssey 9.507, it is the Cyclops’ response to hearing that the man who has blinded him is called Odysseus (as foretold), and at 13.172, Alcinous, when the ship returning from Ithaca has been turned to stone, recalls his father’s prediction that Poseidon would one day punish the Phaeacians for giving safe conduct across the sea. For audiences familiar with Homer, these associations might give extra significance to Oedipus’ words at 450-2. 
(d) Dealing with the oracles
When Theseus arrives (551), Oedipus is able to draw out more fully than he could earlier (72-4, 287-8) the implications of his being received, and buried, in Attica. Theseus is puzzled to hear that although Oedipus’ sons are unwilling to receive him back at Thebes, or bury him there after his death, because of his having killed his father, they are still intent on removing him from Athens, and he asks (602) “How then would they send for you, on condition of your living separately (from them, i.e. not in Thebes)?” sc. “What would be the point of their sending for you?” to which Oedipus replies, “The divine mouth will compel them” (τὸ θεῖον αὐτοὺς ἐξαναγάσει στόμα, 603).  The expression may sound vague, but what Oedipus means is “an oracle” or “the oracle,” and Theseus sees the point: “What sort of disaster might oracles make them fear?” (604). The audience has heard about Oracle B (387-417), and there is no need for Oedipus to go into much detail here. The situation as he sees it is that the Thebans want him close to their border because they are afraid they will incur his posthumous anger, instead of gaining his protection, if they fail to give him regular observance, and he now ventures an interpretation of Ismene’s words at 402 and 411 in the light of his hope to be buried in Attica by Theseus: the only way for the Thebans to ensure regular access is if they have his burial place as near as possible to their own territory, whereas if it is far away under another city’s control there is no knowing what conflicts may arise.
The answer given by Oedipus at 605 to Theseus’ question “What sort of disaster…?” is “that it (is) necessary/fated for them to be struck in this land” (ὅτι σφ᾽ ἀνάγνκη τῆιδε πληγῆναι χθονί). Oedipus is not explicit about what kind of disaster might strike, or who might be responsible, and Theseus understandably asks more questions, which Oedipus answers with his great speech on time and change (607-28). What Oedipus predicts is that at some future time, and on some small pretext, the present firm alliance between Thebes and Athens may be broken, and if and when it is, Oedipus will protect the Athenians (because they are giving him due honours), and his “cold corpse will drink the Thebans’ hot blood, if Zeus is still Zeus and Phoebus son of Zeus is clear” (… εἰ Ζεὺς ἔτι Ζεὺς χὠ Διὸς Φοῖβος σαφής 621-3). Oedipus sums up the source of his conviction: Apollo’s oracles (which derive from Zeus: cf. Aeschylus Eumenides 614-21), the most reliable authority he can cite. No verb is expressed in this conditional clause: “if Zeus (is) still Zeus and Phoebus son of Zeus (is) true” (literally “clear”; for σαφής in prophetic contexts cf. 792 and OT 1011). This is an assertion expressed as a condition, but implying certainty: “if, as I believe to be the case…” or “as sure as…”; as at 628, “if the gods do not deceive me” (εἴπερ μὴ θεοὶ ψεύδουσί με), and 1381-2. From Oedipus’ point of view there is no doubt that he has rightly interpreted the oracles, but for Theseus and the Chorus what he says has to be taken on trust. Oedipus is offering a prediction, based on his reading of the oracles, which could perhaps be understood by a late fifth-century audience as relating to recent events, while for Theseus (631-41, 664-5) and the Athenians (629-30) it is has the authority of someone who evidently has special insight into the meaning of oracular utterance.
At 624 Oedipus pointedly refrains from being any more explicit about the future and discourages Theseus from questioning him, “since it (is) not pleasing to utter words not to be disturbed” (ἀλλ᾽ οὐ γὰρ αὐδᾶν ἡδύ τἀκίνητ᾽ ἔπη).  These mysterious words will turn out to be instructions which Oedipus knows he must save for his final moments, relating to the secret that only Theseus must witness (cf. 1520-32, especially 1526-7). A new idea of great importance for the rest of the play is introduced here: instructions (presumably deriving from hints in Oracle A that have not already been revealed?). But it is held in suspense until overtures from the Theban side have been heard and rejected.
First comes Creon with an armed retinue, ostensibly representing “the city,” but clearly acting as spokesman for Eteocles (as Ismene has implied at 396- 400), then later Polyneices, presenting himself as a suppliant at Athens like his father. Both seem to rely on Theban interpretations or versions of Oracle B, though Creon makes no mention of it, and Polyneices has only a couple of brief references, but there is no doubt that it is their understanding of the oracular message, and this alone, that has prompted both visits.
When Creon arrives (728) Oedipus is reticent for a start about what he knows, and Creon, unaware that Oedipus has already been told by Ismene of Oracle B, makes him a hypocritically welcoming offer to “come home,” with no reference to the conflict between Eteocles and Polyneices and no mention of his having to be kept outside Theban territory. Oedipus, of course, is able to denounce Creon’s real intentions, on the strength of what he claims to know from “Phoebus and Zeus” (793), that is, from Oracles A and B, and particularly the part of Oracle A unknown to the Thebans. But the tables are unexpectedly turned when Creon uses force: he has already kidnapped Ismene (818-21), now takes Antigone (826-47), and threatens Oedipus himself (858-83). Clearly the oracles leave gaps in their mapping of the future, and everything depends at this juncture on the action of Theseus and his troops, who duly rescue Antigone and Ismene and bring news of the suppliant at Poseidon’s altar.
Polyneices has the difficult task of trying to get Oedipus to speak to him, and sets out the situation as he understands it (1291-1325): he has been driven into exile by his brother Eteocles, with the city’s support, because he claimed his right as the elder  to succeed to Oedipus’ royal power. The responsibility for this quarrel, Polyneices claims, is mainly to be attributed to Oedipus’ “Erinys” (1299),  which should probably be understood quite generally in terms of his family’s inherited troubles, as in Ismene’s reference at 369-71 to the “the ancient blight on the family” (τὴν πάλαι γένους φθοράν, which the brothers initially tried to avert by letting Creon continue to rule), and in Oedipus’ similar remark to Creon at 964-5. At 1300 Polyneices goes on to add, “Then I hear from seers, too, in the same sense,” and quickly moves on to the list of the distinguished comrades he has enlisted to help him attack Thebes.  This single verse sounds rather vague and perhaps embarrassed, but when he refers more explicitly to oracles at 1331-2 he claims that whichever side Oedipus favours in the coming conflict will have the power (kratos), in language that recalls other formulations of Oracle B (cf. n.7 above), while for Oedipus himself the reward will be return to Thebes, with nothing said now about the need for him to be kept outside the frontier. Power is the dominant motif here, and the interpretation of the oracle is narrowly focused on the quarrel between Oedipus’ sons, and the question of who will win the coming battle, which seems to be the only reason why either of them is belatedly taking an interest in his welfare.
Oedipus’ terrifying speech in reply begins at 1348ff. with denunciation of Polyneices’ past failures to support his father, then at 1370-5 moves into prophecy: Polyneices will not be successful in his attack on Thebes, and instead the two brothers will kill one another. This echoes the conclusion he drew at 450-4 from what Ismene told him, and as early as 421-7 her news had already prompted him to wish failure on them both. Now at 1375 he summons those curses  to be his allies, along with the “darkness of Tartarus,” the goddesses of the grove, and Ares. Polyneices prepares to leave in utter despair.
Antigone’s response is crucially different from her brother’s (1413-37). She tries to persuade him to take his army back to Argos and not destroy himself and his city, pointing out that he will gain nothing from ruining his native land. When Polyneices refuses, on the grounds that he cannot face the shame of giving up, she uses the language of prophecy to speak of Oedipus’ curses: “Do you not see that you are fulfilling his manteia“? And she goes on to ask, “How will anyone who hears what Oedipus foretold (ethespisen) dare to follow you”? This shows that she does not take Oedipus’ words as inevitably going to be fulfilled, a “magic” process that cannot be evaded. Her brother simply answers that he will not tell his comrades the bad news; he sees himself set on a path that has been made ill-fated and evil by his father and his Erinyes (1432-4). This poignant little scene brings out all too sharply the complexity of the relations between oracular knowledge and “destiny”: Polyneices could indeed now retreat and disband the expedition, but his actions will show him collaborating with the manteia/curses in what he believes is his doom, just as Eteocles does in Aeschylus, when he has heard that he will be facing his brother at the seventh gate, and the Chorus, with perfectly sound arguments, try to stop him (Seven against Thebes 683-719).
(e) Revelations and secrets
Moments after Polyneices leaves, the Chorus hear a sudden clap of thunder, which Oedipus recognises as the beginning of the promised signs (1460), marking the urgent need for Theseus to be sent for; another peal and a lightning flash confirm his interpretation (1472-3: “my prophesied (thesphatos) end has come”), and another (1478-9) makes Oedipus all the more anxious for Theseus to arrive while he is still alive and able to pass on his vital instructions. When Theseus does come he confirms that this is the critical moment: “my life is in the balance/ at its turning point” (1508); Theseus asks what “evidence” he is relying on, to which Oedipus replies, “The gods themselves are heralds bringing the message, in no way cheating (me) of the signs appointed beforehand” (1511-12). So the action has reached its final phase: Oracle A, with its final intimations only cryptically revealed up to now (cf. the end of section (c), above) provides the model for the action of the play, and it is becoming clear that all the prophecies we have heard have related to the same mysterious outcome. Theseus at once understands that this is no ordinary thunderstorm: he has heard Oedipus “making many predictions” (thespizonth’), “and they have not been false utterances” (pseudophêma) (1516-17). 
The essential dramatic point in relation to Oedipus’ secret is that, although he knows he has something to give to Theseus, having identified in general terms the place where he is to meet his end (the grove of the Semnai), and the signs that will announce it (mentioned at 94-5), he still does not know precisely when, where and in what way the summons will come or just what will happen then. This explains why he has been so anxious to stay where he is, in order to avoid being in the wrong place at the crucial moment. Hence his concern in earlier scenes to send Creon and Polyneices away, and now to get Theseus back at the right time. Only when the final stage begins to happen does he know that it is happening.
Now Oedipus can give Theseus his crucial instructions (1518-38), including how to deal with the secret information that he will receive for the future protection of Athens, namely the exact location of his death, which Theseus alone will witness and must reveal only to his successor, when he himself is on the point of dying. 1526-9 are particularly telling: “But as for things that are exagista and (of a kind) not disturbed by speech, you yourself will learn them, when you go (there) alone.” The implication of exagista is “banned,” “taboo,” of things too sacred and secret to be put into words. This recalls the extreme circumspection with which the Semnai and their grove are treated, as when the Chorus describe (in more or less untranslatable language) their intense veneration and dread of the goddesses: “… whom we tremble to mention, and we go past (them) without looking, without sound, without words, moving our lips in mutely reverent thought” (129-33). The goddesses are too fearsome to have their names uttered in worship, and any name by which one refers to them has to be a euphemism (as at 84, when Oedipus addresses them as “ladies of terrifying gaze”). 
Oedipus’ parting words and actions (1539-55), when he feels the presence of divine forces enabling him to lead the way unguided for his daughters and Theseus, enact the fulfilment of what he has been told by the oracle to wait for, without suggesting that there was a specific set of verbal clues that had to be decoded. The implication, indeed, of his taking the lead (1542-6) is that he somehow knows where he must go, but without the aid of normal sight or any previous knowledge of the locality. Similarly, in the great messenger speech that describes Oedipus’ passing,  there is ample evidence of supernatural involvement (more thunder, 1606, a divine voice calling him, 1623-6), but no clue to what Theseus saw in the final moments (cf.1645-55) and no clue, therefore, to precise interpretation. But the desire for interpretation is strongly stressed, even though the messenger cannot satisfy it: the best he can do is to say what did not happen (there was no thunderbolt or whirlwind to make Oedipus vanish), and to speculate that there might have been some escort from the gods, or the earth itself opening for him. At any rate, the messenger is sure that there was no lamentation, no sickness and suffering, but something uniquely “wonderful” (thaumastos, 1663-5; cf.1586). So the secret is to remain a secret, and Theseus confirms (1760-7) that he is forbidden to divulge what he has seen. But the preservation of the secret—and hence the safety of Athens—are precariously contingent on human fidelity in passing it on from generation to generation.
(f) Making sense
I have been arguing in this paper that there is great subtlety in the use that Sophocles makes of the language of oracles, giving it a logic that we can try to follow, but at the same time eluding certainty or explanation. One thing that emerges very strongly from a survey of this language is that the central role of interpreter is played by Oedipus himself. As solver of the riddle of the Sphinx, whose life has been dogged by oracles and by the sufferings entailed in his efforts to understand them,  he knows something about interpretation, and the play’s vocabulary, in addition to using much “regular” oracular language, has some distinctive features that reinforce this approach.
The idea of “the watchword of my fate/ of what happens to me” (ξυμφορᾶς ξύνθημ ἐμῆς) at 46 is a strong marker early in the play that some very close attention will need to be paid to words and names; at 94, Oedipus uses a word with similar metaphorical connotations: Apollo “passed the watchword” (παρηγγύα), and so “indicated” the signs (σημεῖα) that he was to look out for. At 398, in the tense exchange with Ismene, when Oedipus is learning about the Theban responses to oracles, he asks her to “interpret for me” (ἑρμήνευέ μοι), and at 453 he uses the uncommon word συννοῶν to stress the notion of putting together, and thinking about, two sets of information. The same idea recurs at 1473-4, when Oedipus has heard the thunder and announces that his prophesied end has come, and Antigone asks him ” How do you know? On what (sign/evidence?) have you inferred this”? (τῶι δὲ τοῦτο συμβαλὼν ἔχεις;). By this stage he feels confident that his interpretations have been correct, and all he answers is “I understand very well” (καλῶς κάτοιδ᾽), but there is still much that he cannot put into words. Oedipus’ example can perhaps teach us to accept the limits of human understanding, and, as critics, to allow for a range of possible ways of interpreting what the oracles, and the play, might mean. 
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Bushnell, R.W. 1988. Prophesying Tragedy: Sign and Voice in Sophocles’ Theban Plays. Ithaca.
Cairns, D. and Liapis,V., eds, 2006. Dionysalexandros: Essays on Aeschylus and his Fellow Tragedians in Honour of Alexander F. Garvie. Swansea.
Dawe, R.D. 1978. Studies on the Text of Sophocles, Vol.3. Leiden.
Easterling, P.E. 2006. “The Death of Oedipus and What Happened Next”, in Cairns and Liapis 2006:133–150.
Edmunds, L. 1996. Theatrical Space and Historical Place in Oedipus at Colonus. Lanham, MD.
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[ back ] 1. 1 Nagy 1994:7; cf. on p.6: “the god who primarily presides over speech-acts, which are then ratified by the actual course of events, is Apollo. It is for this reason that he presides over oracles, including the great Oracle at Delphi.”
[ back ] 2. 2 Another word sometimes used for prophetic utterance is omphê, as at 102: κατ᾿ ὀμφὰς τὰς Ἀπόλλωνος. At 550 and 1351 it is used of Oedipus’ (significant) words; cf. Kavoulaki 2009: 244. At 388 thespizô “prophesy” is applied to oracular messages; at 1428 and 1516 Oedipus is the subject of the verb.
[ back ] 3. 3 For a careful distinction between Apollo and Apollo’s ministers cf. OT 711-12.
[ back ] 4. 4 The cult of the Eumenides was known in different parts of Greece; the title Semnai Theai was specifically Attic. Cf. Henrichs 1994: 39-50, who points out that these and other titles, e.g. potniai at Thebes, were all euphemisms for names not to be uttered; the Erinyes as such did not receive cult.
[ back ] 5. 5 The terms of his question are not spelled out: all we are told is that Apollo [ back ] sent him away without vouchsafing an answer to what he had come for (ὧν μὲν ἱκόμην | ἄτιμον ἐξέπεμψεν 788-9).
[ back ] 6. 6 The subject of φασί is not specified, but the reference is presumably to what “people” say, on the strength of reports of the oracle.
[ back ] 7. 7 There is insistent use here, echoing 373 and 392, of words associated with power and control (kratos and related forms): at 400 κρατῶσι is used of the Thebans in relation to Oedipus, and at 405 they will keep him close to the border, and “not where you would have power over yourself ” μηδ᾿ ἵν᾿ ἂν σαυτοῦ κρατοῖς; cf. 408. The theme is recalled at important moments later in the play: 646, 1331-2, 1380-2.
[ back ] 8. 8 Cf. Women of Trachis 608-9, 1192; Aeschylus Persians 686, of the elders standing close to the tomb of Darius: ὑμεῖς δὲ θρηνεῖτ᾿ ἐγγὺς ἑστῶτες τάφου. At Aeschylus Agamemnon1037-8 Clytemnestra speaks of Cassandra standing among the many slaves at the household altar.
[ back ] 10. 10 Cf. Markantonatos 2002: 121, n.7 on the importance of not “reading ahead.”
[ back ] 11. 11 The text transmitted in all the MSS, συννοῶν τά τ᾿ ἐξ ἐμοῦ | παλαίφαθ᾽, is less convincing, though accepted by many editors (who read τε τἀξ instead of τά τ᾿ ἐξ, so as to place τε in a more logical position, immediately following συννοῶν). This has to be understood as “and reflecting, too, from myself (sc.from my own memory?), on the pronouncements made long ago,” but it diverts attention from the notion that Oedipus has only just arrived at a fuller understanding of what Apollo prophesied in the past (87-93). See Lloyd-Jones and Wilson 1990: 231 for a defence of Heimsoeth’s τε θέσφατα.
[ back ] 12. 12 The future “will compel” (ἐξαναγκάσει) implies not a fresh oracle, but one that has already been given, whose effects lie in the future.
[ back ] 13. 13 Cf. Teiresias at Antigone 1060 with Bushnell 1988: 98-9.
[ back ] 14. 14 This is a striking reversal on Sophocles’ part (already emphasised at 374-6 and mentioned again at 1422-3) of the order of seniority adopted at Euripides’ Phoenician Women 71-2. For the earlier tradition, see Mastronarde 1994: 27 with n. 20, Sommerstein 2010: 82-8.
[ back ] 15. 15 Cf. Eteocles at Aeschylus Seven against Thebes 70, but there the emphasis is on a curse already uttered by Oedipus; cf.n.18 below. OC makes very significant changes to the story; cf.n.14 above.
[ back ] 16. 16 The authenticity of this verse has been doubted. Reeve 1973: 290 proposes deletion, and Dawe 1978: 146 argues for a lacuna between 1300 and 1301; but West 1981: 526-7 makes a convincing case for the sense and syntax of the text as it stands.
[ back ] 17. 17 There has been much debate about the implication of prosthe at 1375: does this refer to Oedipus’ words at 421-7, or to some earlier curse? I agree with Mastronarde 1994: 24 that “the curse in OC seems to emerge from the circumstances of the play itself.”
[ back ] 18. 18 Theseus has been convinced, for example, by Oedipus’ intimation of future changes in Theban/Athenian relations, and has witnessed him exposing Creon’s deceitfulness.
[ back ] 19. 19 The theme of utterance/non-utterance is recurrent in this play: e.g. 486-9, part of the instructions for the ritual of purification performed by Ismene on Oedipus’ behalf, specifying the content of the prayer, which must be apusta,”not to be heard,” that is, by anyone except the goddesses. Linked with them are the Great Goddesses, Demeter and Kore, mentioned several times in the play as protective presences in Attica, whose mysteries are strikingly evoked in the description of Eleusis at 1050-3, “where the potniai nurse the awesome (semna) rites for the mortals on whose tongue rests the golden key [ back ] of the Eumolpidai.”
[ back ] 20. 20 For a fuller discussion of this speech cf. Easterling 2006.
[ back ] 21. 21 As he points out to Creon at 969-76.
[ back ] 22. 22 For interesting discussion of these issues see e.g. Knox 1964; Burian 1974; Segal 1981; Bushnell 1988; Budelmann 2000: 187-94; Guidorizzi in Avezzù, Guidorizzi, and Cerri 2008.