Passage 3.24.11
Ὅμηρος δὲ ἔγραψε μὲν τῆς ποιήσεως ἀρχόμενος ὡς Ἀχιλλεὺς χαριζόμενος τοῖς Ἀτρέως παισὶ καὶ οὐκ ἐνεχόμενος τοῖς ὅρκοις τοῖς Τυνδάρεω παραγένοιτο ἐς Τροίαν, ἐποίησε δὲ ἐν ἄθλοις λέγοντα Ἀντίλοχον ὡς Ὀδυσσεὺς πρεσβύτερός ἐστιν αὐτοῦ γενεᾷ, τὸν δὲ Ὀδυσσέα πρὸς Ἀλκίνουν περὶ τῶν ἐν Ἅιδου καὶ ἄλλα διηγούμενον καὶ ὅτι Θησέα ἰδεῖν ἐθελήσαι καὶ Πειρίθουν προτέρους ἄνδρας ἢ καθʼ ἡλικίαν τὴν αὑτοῦ· Θησέα δὲ ἴσμεν ἁρπάσαντα Ἑλένην. οὕτως οὐδὲ ἐγχωροῦν ἐστιν ἀρχὴν Ἑλένης μνηστῆρα Ἀχιλλέα γενέσθαι.
Homer, indeed, wrote at the beginning of his poem that Achilles came to Troy as a favor to the sons of Atreus and was not bound by the oath sworn to Tyndareus. Furthermore, he depicted Antilochus during the funeral games stating that Odysseus is older than himself by a generation, and he has Odysseus narrating to Alcinous, among other accounts of his experiences in Hades, how he desired to see Theseus and Peirithous, men who belonged to an earlier generation than his own. We know that Theseus had carried off Helen. It is therefore impossible even on chronological grounds that Achilles should have been a suitor for Helen.