Acts 10:48

And he commanded them to be baptized in the name of the Lord. Then prayed they him to tarry certain days.

The Lord, in this instance, had evidently planned to give an unusual demonstration of His power. For as Peter was still uttering the last impressive words of his discourse, the Holy Spirit fell upon, and filled, all those that were listening to the preaching of the Word. They had been believers in the coming Messiah before, in the Christ that was to bring redemption to the Jews; they were now believers in the Christ that had died for them on Calvary, whose full salvation had been earned for them. And the Holy Spirit was imparted to them in extraordinary measure, in such a way, in fact, as to cause the greatest astonishment in all the Jews that were present, in Peter as well as in the members of the congregation at Joppa. Here they had visible evidence of the fact that the Gentiles were indeed acceptable to the Lord, for the Spirit even gave them the gift of tongues, thus enabling them to praise and magnify the God of their salvation in languages which had been unknown to them before that day. See chap. 11:17. It was not mere jubilant ecstatic praising of God which Luke here records, but a repetition of the Pentecost miracle, although probably not on so great a scale. Peter, at any rate, was fully convinced. He voiced his feelings in the emphatic rhetorical question: Surely no one present would want to hinder the water that these men might not be baptized! There could be no possible reason for refusing to accept these men into the Christian Church in whose case the Lord had so plainly indicated that the Gentiles also should find admission into the kingdom of Christ. All difference between Jews and Gentiles has been removed by the death of Jesus. Full salvation and all the gifts of the Holy Ghost are ready for all the world, for all that will but accept these blessings with the hand of faith. And so Peter, who, in this instance, did not baptize himself, now gave the order, entrusting its execution probably to Philip the Evangelist, whose labors extended to this city, that they should be baptized in the name of Jesus Christ, and thus be sealed with all the heavenly blessings which the Savior has gained and appropriates through the water of Baptism. No wonder that Cornelius and his friends, after this experience, earnestly begged Peter to remain with them a little longer, to spend some time with them, at least a number of days. They were anxious to hear more of the wonderful testimony concerning Jesus the Savior.

Summary

Peter, having been called to Caesarea by Cornelius and prepared for the visit by a special vision from heaven, preaches the Gospel to the Gentiles, who thereupon receive the Holy Ghost and are baptized.