Diodorus Siculus, Bibliotheca Historica 4.25.1
1 ...παρῆλθεν εἰς τὰς Ἀθήνας καὶ μετέσχε τῶν ἐν Ἐλευσῖνι μυστηρίων, Μουσαίου τοῦ Ὀρφέως υἱοῦ τότε προεστηκότος τῆς τελετῆς.
2 ἐπεὶ δ’ ’Ορφέως ἐμνήσθημεν, οὐκ ἀνοίκειόν ἐστι παρεκβάντας βραχέα περὶ αὐτοῦ διελθεῖν. οὗτος γὰρ ἦν υἱὸς μὲν Οἰάγρου, Θρᾶιξ δὲ τὸ γένος, παιδείαι δὲ καὶ μελωιδίαι καὶ ποιήσει πολὺ προέχων τῶν μνημονευομένων· καὶ γὰρ ποίημα συνετάξατο θαυμαζόμενον καὶ <τῆι <τῆι> Dindorf> κατὰ τὴν ὠιδὴν εὐμελείαι διαφέρον. ἐπὶ τοσοῦτο δὲ προέβη τῆι δόξηι ὥστε δοκεῖν τῆι μελῳδίᾳ θέλγειν τά τε θηρία καὶ τὰ δένδρα.
3 περὶ δὲ παιδείαν ἀσχοληθεὶς καὶ τὰ περὶ τῆς θεολογίας μυθολογούμενα μαθών, ἀπεδήμησε μὲν εἰς Αἴγυπτον, κἀκεῖ πολλὰ προσεπιμαθὼν μέγιστος ἐγένετο τῶν Ἑλλήνων ἔν τε ταῖς θεολογίαις καὶ ταῖς τελεταῖς καὶ ποιήμασι καὶ μελωιδίαις.
4 συνεστρατεύσατο δὲ καὶ τοῖς Ἀργοναύταις, καὶ διὰ τὸν ἔρωτα τὸν πρὸς τὴν γυναῖκα καταβῆναι μὲν εἰς ιδου παραδόξως ἐτόλμησε, τὴν δὲ Φερσεφόνην διὰ τῆς εὐμελείας ψυχαγωγήσας ἔπεισε συνεργῆσαι ταῖς ἐπιθυμίαις καὶ συγχωρῆσαι τὴν γυναῖκα αὐτοῦ τετελευτηκυῖαν ἀναγαγεῖν ἐξ ιδου παραπλησίως τῶι Διονύσωι· καὶ γὰρ ἐκεῖνον μυθολογοῦσιν ἀναγαγεῖν τὴν μητέρα Σεμέλην ἐξ ιδου, καὶ μεταδόντα τῆς ἀθανασίας Θυώνην μετονομάσαι.
1 [Heracles] came to Athens and took part in the Eleusinian mysteries, Musaeus, the son of Orpheus, then being in charge of the rite.
2 But since we have mentioned Orpheus, it is not unfitting for us to make a digression and give a brief account about him. He was the son of Oeagrus, a Thracian in origin, far surpassing those on record in his education, his singing, and his poetry. Indeed, he composed a marvelous poem whose song had a remarkable melody. His reputation became so great that he was thought to bewitch even beasts and trees with his music.
3 After he had devoted himself to study and had learned the mythical stories whose subject matter is theological, he moved to Egypt, and there, having learnt much in addition, he became the greatest of the Greeks in praises of the gods and in initiations as well as poems and melodies.
4 He also took part in the Argonautic expedition and, on account of love for his wife, he dared to descend to Hades—incredibly—and having ensorcelled Persephone through his melodious singing, he persuaded her to cooperate with his desires and to allow him to lead his dead wife up out of Hades—just like Dionysus. For in myth they say that he, too, led his mother Semele out of Hades and that, after he had given her a share of immortality, he re-named her Thyone.