Ἔθυε τῷ Ποσειδῶνι ὁ Πελίης, καὶ προεῖπε πᾶσι παρεῖναι· οἱ δὲ ἤϊσαν οἵ τε ἄλλοι πολῖται καὶ ὁ ’Ιήσων. ἔτυχε δὲ ἀροτρεύων ἐγγὺς τοῦ Ἀναύρου ποταμοῦ, ἀσάμβαλος δὲ διέβαινε τὸν ποταμόν, διαβὰς δὲ τὸν μὲν δεξιὸν ὑποδεῖται πόδα· τὸν δὲ ἀριστερὸν ἐπιλήθεται, καὶ ἔρχεται οὕτως ἐπὶ δεῖπνον. ἰδὼν δὲ ὁ Πελίης συμβάλλει τὸ μαντήϊον, καὶ τότε μὲν ἡσύχασε, τῇ δ’ ὑστεραίῃ μεταπεμψάμενος αὐτὸν ἤρετο ὅ τι <ἄν> ποιοίη εἰ αὐτῷ χρησθείη ὑπό του τῶν πολιτῶν ἀποθανεῖν· ὁ δὲ Ἰήσων, πέμψαι ἂν εἰς Αἶαν αὐτὸν ἐπὶ τὸ κῶας τὸ χρυσόμαλλον, ἄξοντα ἂν ἀπὸ Αἰήτεω. ταῦτα δὲ τῷ Ἰήσονι Ἥρη ἐς νόον βάλλει, ὡς ἔλθοι ἡ Μήδεια τῷ Πελίῃ κακόν.
(Pherecydes of Athens, fr. 105)

Pelias was sacrificing to Poseidon, and summoned all to attend. Among the citizens who came was Jason. He happened to be ploughing near the river Anauros, which he crossed without his sandals on; once across he tied on the right one, but forgot the left, and thus he came to the feast. Pelias saw him and understood the oracle. For the time being he kept quiet, but the next day he sent for him and asked what he would do if he had an oracle saying that one of the citizens would kill him; Jason replied that he would send him to fetch the golden fleece from Aietes. Hera put this in Jason’s mind so that Medea’s arrival would spell doom for Pelias. (tr. Robert Louis Fowler)