“Peter Rose Up.” (Homilies on Acts of Apostles, Benedictine Edition, Iii., Tom. Ix., P. 23.)
And in those days Peter rose up in the midst of the disciples and said. As one eager and as entrusted by Christ with the flock, and as the first of the choir, he ever first begins to speak. And the number of names together was, he says, about a hundred and twenty. Men and brethren, this Scripture must needs have been fulfilled, which the Holy Ghost spake before. Why then did he not singly ask of Christ to give him some one in the place of Judas? And why do they not make the election of themselves? Peter had now become better than his old self. This is what we may say on the subject. We will give two reasons why their asking for one to fill up their band was no chance but a matter of revelation: the first, that they were engaged about other things; the second, that this was the greatest proof of Christ’s presence with them. For being absent He made the election as He would have done if present. And this was no small matter of consolation. But observe Peter doing this with common consent; nothing authoritatively, nothing arbitrarily. And he did not say simply thus: ‘Instead of Judas we elect this man,’ but consoling them about what had passed, see how he manages his discourse. For what had happened had caused no small distress. And do not wonder at this. For if many at present twist about this fact, what may we expect that they said? Men and brethren, he says: if the Lord called them brethren, how much more he?... This is why he began by saying, Men and brethren, we must choose one of us. He commits the judgment to the multitude, both to invest with respect those who were chosen, and to escape himself odium from the rest.... What, then, might not Peter himself have elected? Certainly. But he does not do so, that he might not seem partial. Moreover, he had not as yet received the Spirit. And they appointed two, Joseph that is called Barsabas and Matthias. He did not appoint them, but all. He introduced the matter, showing that it was not even his own, but from above, according to prophecy. So that he was an interpreter, not a master.