Acts 1:21

“"Wherefore it behooves of these men which have companied with us all the time." Why does he make it their business too? That the matter might not become an object of strife, and they might not fall into contention about it. For if the Apostles themselves once did this, much more might those. This he ever avoids. Wherefore at the beginning he said, "Men and brethren. It behooves" to choose from among you. He defers the decision to the whole body, thereby both making the elected objects of reverence and himself keeping clear of all invidiousness with regard to the rest. For such occasions always give rise to great evils. Now that some one must needs be appointed, he adduces the prophet as witness: but from among what persons: "Of these," he says, "which have companied with us, all the time that the Lord Jesus went in and out among us, beginning from the baptism of John unto that same day that He was taken up from us, must one be ordained to be a witness with us of His resurrection": that their college might not be left mutilated. Then why did it not rest with Peter to make the election himself: what was the motive? This; that he might not seem to bestow it of favor. And besides, he was not yet endowed with the spirit. "Wherefore of these men which have companied with us," continues Peter. Observe how desirous he is they should be eye-witnesses. It is true indeed that the Spirit would shortly come; and yet great care is shown with regard to this circumstance. "Of these men," he says, "which have companied with us, all the time that the Lord Jesus went in and out among us." He shows that they had dwelt with Christ, not simply been present as disciples. In fact, from the very beginning there were many that then followed Him. "All the time," he says, "that the Lord Jesus went in and out among us, beginning from the baptism of John." True! for no one knew what preceded that event, though they did learn it by the Spirit. "Unto that same day that He was taken up from us, must one be ordained to be a witness with us of His resurrection." He said not, a witness of the rest of his actions, but a witness of the resurrection alone. For indeed that witness had a better right to be believed, who was able to declare, that He Who ate and drank, and was crucified, the same rose again. Wherefore it was needed that he should be a witness, not only of the time preceding this event, nor only of what followed it, and of the miracles; the thing required was, the resurrection. For the other matters were manifest and acknowledged, but the resurrection took place in secret, and was manifest to these only. And they do not say, Angels have told us; but, We have seen. For this it was that was most needful at that time: that they should be men having a right to be believed, because they had seen.”

“He presents the matter as shared with the brethren, so that it would not meet with objections and would not give occasion for disputes. Therefore at the beginning of the discourse he also said: "Men and brethren, it is necessary to choose from among you," — entrusting the choice to all, and at the same time granting honor to those chosen, and freeing himself from reproach on the part of anyone whatsoever. And that this is how it had to be, he himself says and brings a prophet as witness. From whom was the choice to be made? "From those who were with us the entire time." He says this because it necessarily had to be so. And he did not say: "from honorable men who are with us," because then it would have seemed that he was insulting the rest. But now the matter was decided by time.”

“Peter announces to them, so that the matter may not become a subject of bitter contest, and that they may not fall into quarreling. For this reason he also begins, "Men, brothers," he says, "it is necessary to choose from among you, entrusting the decision to the multitude, and at the same time making the chosen ones respectable, and freeing himself from hate toward the others." And that which needed to happen, he even introduces by quoting the prophet: "Another will take his office." (Ps. 109:8) But from whom must he be chosen? From those who, by their assembly with them, have shown themselves tried over time. Therefore he did not even say "from the respectable," so as not to seem to insult the others.”