Letter 78: Procopius says the young men's own character confirmed Irenaeus's recommendation.

At first, it was you who created my goodwill toward the young men around Zonaios. After I had experience of them, their own nature did the same. Having gained the first favor because of you, they finally won my affection through themselves. Seriousness adorns their character, and their nature knows how not to put that seriousness to shame. If you had not told me beforehand, I might perhaps have guessed that they were connected with you by birth, judging from the stamp of their nature. Good indeed is your family, if it knows how to produce such people. Know, then, that my judgment is strong on behalf of the young men. Whether I also have power to assist my eagerness lies in the lap of the gods.

Εἰρηναίωι Τοῖς περὶ Ζώναιον τὴν ἐμὴν εὔνοιαν ἐνεποίει, τὸ μὲν πρῶτον ὑμεῖς, μετὰ δὲ τὴν πεῖραν τῶν νέων ἡ φύσις. καὶ τῶν πρώτων διὰ σὲ τυχόντες, τὸ τελευταῖον οὕτω μοι δι' αὑτοὺς ἐνεποίουν τὸν ἔρωτα. κοσμεῖ γὰρ αὐτοὺς τὸν μὲν τρόπον σπουδή, τὴν δὲ σπουδὴν οὐκ ἐλέγχειν οἶδεν ἡ φύσις, ὥστε εἰ μὴ προμηνύσας ἔτυχες, ἴσως ἂν ἐμαντευσάμην ὡς πρὸς σὲ τὸ γένος συνάπτουσι, τῷ χαρακτῆρι τῆς φύσεως στοχασάμενος. ἀλλ' εὖ γε τοῦ σοῦ γένους εἰ τὰ τοιαῦτα τίκτειν ἐπίσταται. τὴν μὲν οὖν ἐμὴν γνώμην ἐρρωμένην ἴσθι τοῖς νέοις· εἰ δὲ καὶ δύναμιν ὑπουργοῦσαν ἔχω τῇ προθυμίᾳ θεῶν ἐν γούνασι κείσθω.