Luke
Acts 10:45ESV·traditional attribution

And the believers from among the circumcised who had come with Peter were amazed, because the gift of the Holy Spirit was poured out even on the Gentiles.

John Calvin Reformed @genevareformer

45. The faithful were astonished. He calleth them faithful who were as yet possessed with a wicked error. So the Lord doth not by and by wipe away all clouds of ignorance from his, and yet they do not darken the praise of faith before God, because he pardoneth errors and doth vouchsafe to favor it, as if it were pure and plain.

Matthew Henry Presbyterian @wholebiblehenry

We have here the issue and effect of Peter's sermon to Cornelius and his friends. He did not labour in vain among them, but they were all brought home to Christ. Here we have, I. God's owning Peter's word, by conferring the Holy Ghost upon the hearers of it, and immediately upon the hearing of it (Act 10:44): While Peter was yet speaking these words...

Commenting on Acts 10:44-48

John Gill Reformed Baptist @doctorgill

And they of the circumcision which believed,.... Or "of the Jews that believed", as the Ethiopic version renders it; the circumcised Jews who believed in Jesus Christ: were astonished, as many as came with Peter; who were six brethren, as appears from Act 11:12 these were amazed, because that on the Gentiles also was poured out of the gift of the Holy Ghost; which they...