Acts 10:48 - Albert Barnes' Notes on the Bible

And he commanded them ... - Why Peter did not himself baptize them is unknown. It might be, perhaps, because he chose to make use of the ministry of the brethren who were with him, to prevent the possibility of future cavil. If they did it themselves, they could not so easily be led by the Jews to find fault with it. It may be added, also, that it seems not to have been the practice of the apostles themselves to baptize very extensively. See 1 Corinthians 1:14-17, “Christ sent me not to baptize, but to preach the gospel.”