And now you also are saved, in a similar manner, by baptism, not by the testimony of sordid flesh, but by the examination of a good conscience in God, through the resurrection of Jesus Christ. (I Peter 3:21)
The flood saved Noah and his family so too baptism saves the baptised. That is the point made by saint Peter in the passage. Thus "baptism now saves you" just a the flood saved Noah and his family. The contrast between "washing away the dirt of the body" and "the answer of a good conscience before God" is between the normal washing that water achieves and the washing of regeneration that is baptism. Saint Peter is not contrasting water in baptism with something spiritual and separated from baptism or something attached to the physical but not part of it.
Matthew Henry comments on this verse with these words:
Noah's salvation in the ark upon the water prefigured the salvation of all good Christians in the church by baptism; that temporal salvation by the ark was a type, the antitype whereunto is the eternal salvation of believers by baptism, to prevent mistakes about which the apostle,
I. Declares what he means by saving baptism; not the outward ceremony of washing with water, which, in itself, does no more than put away the filth of the flesh, but it is that baptism wherein there is a faithful answer or restipulation of a resolved good conscience, engaging to believe in, and be entirely devoted to, God, the Father, Son, and Holy Ghost, renouncing at the same time the flesh, the world, and the devil. The baptismal covenant, made and kept, will certainly save us. Washing is the visible sign; this is the thing signified.
II. The apostle shows that the efficacy of baptism to salvation depends not upon the work done, but upon the resurrection of Christ, which supposes his death, and is the foundation of our faith and hope, to which we are rendered conformable by dying to sin, and rising again to holiness and newness of life. Learn, 1. The sacrament of baptism, rightly received, is a means and a pledge of salvation. Baptism now saveth us. God is pleased to convey his blessings to us in and by his ordinances, Acts ii. 38; xxii. 16. 2. The external participation of baptism will save no man without an answerable good conscience and conversation. There must be the answer of a good conscience towards God.--Obj. Infants cannot make such an answer, and therefore ought not to be baptized.--Answer, the true circumcision was that of the heart and of the spirit (Rom. ii. 29), which children were no more capable of then than our infants are capable of making this answer now; yet they were allowed circumcision at eight days old. The infants of the Christian church therefore may be admitted to the ordinance with as much reason as the infants of the Jewish, unless they are barred from it by some express prohibition of Christ.
III. The apostle, having mentioned the death and resurrection of Christ, proceeds to speak of his ascension, and sitting at the right hand of the Father, as a subject fit to be considered by these believers for their comfort in their suffering condition, 22. If the advancement of Christ was so glorious after his deep humiliation, let not his followers despair, but expect that after these short distresses they shall be advanced to transcendent joy and glory. Learn, 1. Jesus Christ, after he had finished his labours and his sufferings upon earth, ascended triumphantly into heaven, of which see Acts i. 9-11; Mark xvi. 19. He went to heaven to receive his own acquired crown and glory (John xvii. 5), to finish that part of his mediatorial work which could not be done on earth, and make intercession for his people, to demonstrate the fullness of his satisfaction, to take possession of heaven for his people, to prepare mansions for them, and to send down the Comforter, which was to be the first-fruits of his intercession, John xvi. 7. 2. Upon his ascension into heaven, Christ is enthroned at the right hand of the Father. His being said to sit there imports absolute rest and cessation from all further troubles and sufferings, and an advancement to the highest personal dignity and sovereign power. 3. Angels, authorities, and powers, are all made subject to Christ Jesus: all power in heaven and earth, to command, to give law, issue orders, and pronounce a final sentence, is committed to Jesus, God-man, which his enemies will find to their everlasting sorrow and confusion, but his servants to their eternal joy and satisfaction.
Matthew Henry was an English Protestant so I do not endorse all of his comments but it is significant that he along with many of his contemporaries and many Protestants today agree with Catholic teaching insofar as their views relate to baptism being the saving laver of regeneration as the scriptures say and as the Baptised person's death and resurrection with Christ.
