The following is an excerpt from a blog post by John MacArthur entitled Is Baptism Necessary for Salvation. You can read the full blog post HERE.
“It is quite clear from such passages as Acts 15 and Romans 4 that no external act is necessary for salvation. Salvation is by divine grace through faith alone (Romans 3:22, 24, 25, 26, 28, 30; 4:5; Galatians 2:16; Ephesians 2:8-9; Philippians 3:9, etc.).
If water baptism were necessary for salvation, we would expect to find it stressed whenever the gospel is presented in Scripture. That is not the case, however. Peter mentioned baptism in his sermon on the day of Pentecost (Acts 2:38). However, in his sermon from Solomon’s portico in the Temple (Acts 3:12-26), Peter makes no reference to baptism, but links forgiveness of sin to repentance (3:19). If baptism is necessary for the forgiveness of sin, why didn’t Peter say so in Acts 3?
Paul never made water baptism any part of his gospel presentations. In 1 Corinthians 15:1-4, Paul gives a concise summary of the gospel message he preached. There is no mention of baptism. In 1 Corinthians 1:17, Paul states that “Christ did not send me to baptize, but to preach the gospel,” thus clearly differentiating the gospel from baptism.
Those passages are difficult to understand if water baptism is necessary for salvation. If baptism were part of the gospel itself, necessary for salvation, what good would it have done Paul to preach the gospel, but not baptize? No one would have been saved. Paul clearly understood water baptism to be separate from the gospel, and hence in no way efficacious for salvation.
Perhaps the most convincing refutation of the view that baptism is necessary for salvation are those who were saved apart from baptism. The penitent woman (Luke 7:37-50), the paralytic man (Matthew 9:2), the publican (Luke 18:13-14), and the thief on the cross (Luke 23:39-43) all experienced forgiveness of sins apart from baptism. For that matter, we have no record of the apostles’ being baptized, yet Jesus pronounced them clean of their sins (John 15:3–note that the Word of God, not baptism, is what cleansed them).”
No, only the blood of Christ and the renewal of the Holy Spirit can cleanse us from sin.