One of the oldest debates between Christians is whether or not Baptism takes away your sins. On the surface it may not seem like that big of a deal, however, your stance on this issue determines your view on the significance of what Christ did on the cross. Let’s hop right into this. 

Those in favor of infant baptism say that just as circumcision was the outward seal of a Jewish conversion, so water baptism is the seal of a Christian convert (Gen. 15; Gal. 3:8; Col. 2:11-12). Since those of the Old Covenant circumcised their children, those of the New Covenant — or Christians — ought to baptize their children as members of the New Covenant (Matt. 19:14; Acts 2:39; 1 Cor. 7:14). 

Those who oppose infant baptism say one needs to repent and exercise faith in Christ before baptism, and infants obviously are not able to do this. They also argue there are no direct Scriptural references that support infant baptism. Once again, it would seem Christians can legitimately disagree over this issue. 

Is baptism essential for salvation? Well Acts 10 states that some Gentiles were filled with the Holy Spirit (and therefore saved) before they were baptized. This is significant, for the Holy Spirit is the seal of the believer’s salvation (2 Cor. 1:22 “and he has identified us as his own by placing the Holy Spirit in our hearts as the first installment of everything he will give us.”). Furthermore, Jesus saved the thief on the cross without water baptism(Luke 23:43 “I assure you, today you will be with me in paradise.”). It would seem therefore that baptism is not essential for salvation. 

Even though numerous Scriptures speak of the importance of water baptism, adding anything to the work of the cross demeans the sacrifice of the Savior. It implies that His finished work wasn’t enough. But the Bible makes clear that we are saved by grace, and grace alone, "For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast." Ephesians 2:8-9 

Baptism is simply a step of obedience to the Lord following our repentance and confession of sin. Our obedience--water baptism, prayer, good works, fellowship, witnessing, etc.--issues from our faith in Christ. Salvation is not what we do, but Who we have. "He that has the Son has life; and he that has not the Son of God has not life." 1 John 5:12 

While we should preach that all people are commanded to repent and be baptized as mentioned in Acts 2:38, adding any other requirement to salvation by grace becomes "works" in disguise. 

It is important to recognize that baptism is an outward sign of the inward conversionexperience. It identifies us with Christ’s death and with his resurrection (Col. 2:11-12 “When you came to Christ, you were “circumcised,” but not by a physical procedure. It was a spiritual procedure—the cutting away of your sinful nature. ¹² For you were buried with Christ when you were baptized. And with him you were raised to a new life because you trusted the mighty power of God, who raised Christ from the dead.”).At baptism, the believer symbolically dies to the “old man” to become a “brand new creation” in Christ (2 Cor. 5:17). As a sacrament (like Holy Communion), baptism is not absolutely necessary for salvation, but it does established the Christian as a member of God’s visible church. 

But what about Mark 16:16? Mark 16:16 quotes Jesus as saying: "He who believes and is baptized will be saved; but he who does not believe will be condemned.”. Does this mean that salvation is by baptism? 

In no way does this verse establish baptism as a condition for salvation; it is merely the declaration that those who believe and are baptized are saved. Any act of obedience to the Lord could be added after the expression 'whoever believes' and it would remain a true statement, because salvation is the result of faith in Christ. 

It should be noted that when the Lord added, 'but whoever does not believe will be condemned,' there is no mention of baptism. In identifying what would bring about condemnation, Jesus did not say that 'whoever believes but is not baptized shall not be save.' If baptism were necessary for salvation, there are many significant verses which should be amended to read 'you are saved through faith and baptism.' It is clear that faith in Jesus Christ is what saves a person (Acts 16:30-31). 

Baptism is a distinct act of obedience, apart from salvation. This is clarified by the order in which the words 'believe' and 'baptize' occur in the text (cf. Acts 2:38; 10:44-48). Baptism with the Spirit places believers into the body of Christ (1 Cor. 12:13), while water baptism merely signifies to others that a person has professed Christ.

The information for this lesson comes from the book “The Bible Answer Book” by Hank Hanegraaf. ISBN # 0849995442. 
For more information on this and other similar subjects, go to www.equip.org or www.christiananswers.net.