Passage 4.28.8
ἔτι δὲ τοὺς διὰ νεότητα ἐν τοῖς Τρωσὶν ἢ γῆρας οὐχ ὡραίους μάχεσθαι, τούτους μὲν τὸ τεῖχος φρουρεῖν ἔταξε, τῶν ἐν ἡλικίᾳ τοῖς Ἕλλησιν ἐπηυλισμένων· Ἑλλήνων δὲ οἱ τὰ τραύματα ἔχοντες ὁπλίζουσιν αὐτῷ τὸ μάχιμον, ἵνα μηδὲ αὐτοὶ παντάπασιν ἀργοῖεν. τὰ Ὁμήρου μὲν οὖν ὠφέλιμα ἐγένετο ἐς ἅπαντα ἀνθρώποις·
And moreover, those among the Trojans who, due to youthfulness or old age, were unfit to fight, Homer arranged to guard the wall while those of military age were encamped against the Greeks. Likewise among the Greeks, those who had wounds were tasked with preparing arms for the combatants, lest even these men should be altogether idle. Indeed, Homer's works have in every respect proved beneficial to mankind.