John Chrysostom

"When they heard this, they were baptized in the name of the Lord Jesus. And when Paul had laid his hands upon them, the Holy Ghost came on them; and they spake with tongues, and prophesied." The gift is twofold: tongues and prophesyings. Hence is shown an important doctrine, that the baptism of John is incomplete. And he does not say, "Baptism" of forgiveness, but, "of repentance." So that it was likely they had the Spirit, but it did not appear until Paul had laid his hands upon them: then they spake with tongues, etc.

Homily on Acts 40 ↗

Oecumenius

Then, having been baptized into the name of the Lord, he says that by the laying on of Paul's hands they immediately receive the Spirit. But this he did not see; for it is invisible. Yet grace gave some perceptible proof of that operation. And one spoke in the Persian tongue, another in the Roman, another in the Indian, another in some other such language; he uttered speech. And this was revealed to those outside, that the Spirit was in the one who uttered, God showing that this is of the highest authority. [AMMONIUS]

Commentary on Acts ↗

Augustine of Hippo

Did he baptize after a heretic had baptized? Or, if perhaps you dare to say that the friend of the bridegroom was a heretic and was not in the unity of the church, I wish you would write that also. But, if it is complete madness either to think or to say that, then it is the duty of your prudence to reflect on the reason why the apostle Paul baptized after John. …

Letter 93 ↗

Bede

Having heard this, they were baptized in the name of the Lord Jesus. A question is frequently discussed, whether those who, perhaps due to ignorance, were baptized by some who were not themselves baptized, yet were of the right faith, ought to be baptized again; which matter, I think, is explained in this chapter. …

Commentary on Acts ↗