What We Believe About Baptism
Acts 2:37 Now when they heard this, they were cut to the heart, and said to Peter and the rest of the apostles, "Men and brethren, what shall we do?" 38 Then Peter said to them, "Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins; and you shall receive the gift of the Holy Spirit. 39 "For the promise is to you and to your children, and to all who are afar off, as many as the Lord our God will call." 40 And with many other words he testified and exhorted them, saying, "Be saved from this perverse generation." 41 Then those who gladly received his word were baptized; and that day about three thousand souls were added to them.
The Bible states that baptism is "for the remission of our sins". In fact, there are at least 6 verses in the New Testament that directly connect baptism and salvation:
In Mark 16:15, 16 Jesus said “Go into all the world and preach the gospel to every creature. He who believes and is baptized shall be saved”. Jesus presents it as a condition of salvation.
Acts 2:37-38. Ten days after Jesus gave that commandment we read about men who were convicted of their sin and who asked Peter "what shall we do?". Peter's response was “"Repent, and let every one of you be baptized in the name of Jesus Christ for the remission of sins”. Baptism is "for the remission (forgiveness) of our sins".
In Acts 22:16 Saul, the former persecutor of the church was asked, “why are you waiting? Arise and be baptized, and wash away your sins, calling on the name of the Lord.” In baptism our sins are washed away.
Both Romans 6:3 and Galatians 3:27 describe Christians as having been “baptized into Christ”. It is an act of obedience that puts us into Christ. We need to be "in Christ"! Romans 8:1 says "There is therefore now no condemnation to those who are in Christ Jesus".
Finally, 1 Peter 3:21 says “baptism saves you”. In the context (read 20 and 21 together) Peter says that like Noah and his family were saved from the flood in the ark, there is "an antitype which now saves us--baptism". Other versions put it: "and this water symbolizes baptism that now saves you" (NIV), "baptism, which corresponds to this, now saves you" (ESV), the old King James is difficult to read sometimes but it says "The like figure whereunto even baptism doth also now save us" (KJV). Clearly there is some sense in which baptism saves us!
Other texts and examples that support this idea (though not stated it in such direct terms) include: Matthew 28:19-20, John 3:5-6, Acts 8:12-13, Acts 10:47-48, Acts 16:30-34, Acts 18:8, Colossians 2:11-12, Titus 3:3-7. The conversion of the Ethiopian in Acts 8:26-40 is a very good example of someone submitting to water baptism after hearing the gospel.
In the New Testament no one was ever told to just "say the sinners prayer" or “accept Christ”. No one was ever told to wait till some predetermined date to be baptized. In the Bible examples baptism was the normal immediate response of people coming to Jesus.