Acts 2:38

Then Peter said unto them
Being the mouth of the apostles, and being ready to give advice, and speak a word of comfort to their distressed minds:

repent:
change your minds, entertain other thoughts, and a different opinion of Jesus of Nazareth, than you have done; consider him, and believe in him, as the true Messiah and Saviour of the world; look upon him, not any more as an impostor, and a blasphemer, but as sent of God, and the only Redeemer of Israel; change your voice and way of speaking of him, and your conduct towards his disciples and followers; a change of mind will produce a change of actions in life and conversation: bring forth fruits meet for repentance; and make an open and hearty profession of repentance for this your sin. And this the apostle said, to distinguish between a legal and an evangelical repentance; the former is expressed in their being pricked to the heart, on which they were not to depend; the latter he was desirous they might have, and show forth; which springs from the love of God, is attended with views, or at least hopes of pardoning grace and mercy, and with faith in Christ Jesus: it lies in a true sight and sense of sin, under the illuminations and convictions of the Spirit of God; in a sorrow for it, after a godly sort, and because it is committed against a God of love, grace, and mercy, and it shows itself in loathing sin, and in shame for it, in an ingenuous acknowledgement of it, and in forsaking it: and this is moreover urged, to show the necessity of it, as to salvation, for such that God would not have perish, he will have come to repentance; so to their admission to the ordinance of baptism, to which repentance is a pre-requisite; and to which the apostle next advises:

and be baptized everyone of you;
that repents and believes; that is, in water, in which John administered the ordinance of baptism; in which Christ himself was baptized, and in which the apostles of Christ administered it; in this Philip baptized the eunuch; and in this were the persons baptized that were converted in Cornelius's house; and it is distinguished from the baptism of the Spirit, or with fire, the extraordinary gifts of the Spirit mentioned in the last clause of this verse; and which ordinance of water baptism was administered by immersion, as the places, Jordan and Aenon, where John performed it, and the instances of it particularly in Christ, and in the eunuch, and the end of it, which is to represent the death, burial, and resurrection of Christ, as well as the primary signification of the word, show. And this is to be done,

in the name of Jesus Christ;
not to the exclusion of the Father, and of the Spirit, in whose name also this ordinance is to be administered, ( Matthew 28:19 ) but the name of Jesus Christ is particularly mentioned, because of these Jews, who had before rejected and denied him as the Messiah; but now, upon their repentance and faith, they are to be baptized in his name, by his authority, according to his command; professing their faith in him, devoting themselves to him, and calling on his name. The end for which this was to be submitted to, is,

for the remission of sins;
not that forgiveness of sin could be procured either by repentance, or by baptism; for this is only obtained by the blood of Christ; but the apostle advises these awakened, sensible, repenting, and believing souls, to submit to baptism, that by it their faith might be led to Christ, who suffered and died for their sins, who left them buried in his grave, and who rose again for their justification from them; all which is, in a most lively manner, represented in the ordinance of baptism by immersion: the encouragement to it follows,

and ye shall receive the gift of the Holy Ghost:
not the grace of the Spirit, as a regenerator and sanctifier; for that they had already; and is necessary, as previous to baptism; unless it should mean confirmation of that grace, and stability in it, as it appears from ( Acts 2:42 ) they afterwards had; but rather the extraordinary gifts of the Spirit, particularly the gift of speaking with tongues, which Christ had received from the Father, and had now shed on his apostles; see ( Acts 19:5-6 ) .