What is the faith response to the Gospel? That question is determined by the Great Commission. The Great Commission is the charge of Jesus to preach the Good News about redemption in Christ to every person in the world throughout the history of the Christian era. In the context of the Great Commission, Jesus naturally gave the faith response for those who would believe. On every occasion of the giving of the Great Commission, it involved baptism for the remission of sins (Matthew 28:19; Mark 16:15-16; Luke 24:47; John 20:21-23).
Baptism is the essence of the Great Commission. Jesus essentially said to preach and to baptize. Therefore, baptism is the faith response to the Gospel. Notice, for instance, the above-referenced Markan account. “And he said unto them, Go ye into all the world, and preach the gospel to every creature. He that believeth and is baptized shall be saved; but he that believeth not shall be damned” (Mark 16:15-16). And the most powerful biblical proof that baptism is the faith response to the Gospel was on the Day of Pentecost when the Great Commission was fulfilled for the first time.
The Day of Pentecost, recorded in Acts 2, provides us with the greatest and fullest account in the New Testament of the preaching of the Gospel. There, Peter preached to Jews who had previously consented to the crucifixion of Jesus (Acts 2:23). But after the convicting preaching of the death, burial, and resurrection of Jesus, based on Jewish prophecy, the same Jews came to believe in Christ. That is evident from their question in verse 37, “Men and brethren, what shall we do?” That very question is an expression of faith in Christ. By it, they said in effect, “We believe in Him. Now, what shall we do?” Here, Peter applied what Jesus taught in His Great Commission as the faith response to their preaching: “Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.” Notice that when a person is baptized in Jesus’ name, he is promised to receive the Holy Ghost (Acts 2:38-39).
I don’t think the Scriptures could reveal this truth about baptism being the faith response to the Gospel in a plainer way.
Baptism in Jesus’ name, more than any other act, honors Christ and His cross, which makes it possible and, of which, it is a direct result. Nothing else so identifies with the gracious redemption He wrought on Calvary. The very act of baptism mimics Christ’s death, burial, and resurrection and identifies with it in form more than anything else we will ever do.
Notice, too, that baptism is to be administered in the name of Jesus. This is readily evident from a full-orbed study of the Great Commission and its fulfillment on the Day of Pentecost. Use of the name of Jesus is especially important at the point of salvation. It is good and appropriate to make much of the name of Jesus always. It’s good to live everyday by specifically and purposefully giving glory to His name (Colossians 3:17). But the greatest use a person can make of the name of Jesus is being baptized in it and saved by it.
The Bible says, “Glory ye in His holy name: let the heart of them rejoice that seek the LORD” (Psalms 105:3). It is especially appropriate for those initially seeking Christ to glory in the name of Jesus by being submerged into it in baptism, whereby they enter into His mystical death and grave for the washing away of their sins, based on the authority of His saving name (Romans 6:3-5; Acts 22:16; Acts 4:12). It will be wonderful for the rest of their lives to recall that great moment when they were saved by that name* and put on Christ (Galatians 3:27). Nothing so glorifies the name of Jesus as does the act of baptism. He was given the name of Jesus because He would save His people from their sins (Matthew 1:21). Baptism in Jesus’ name does just that in a vital and profound way— by remitting those sins. Peter said baptism is salvific and that it is “the answer of a good conscience before God” (1Peter 3:21). In other words, it is the faith response to the Gospel**.
*Compare similar Old Testament declarations of the saving power of God’s name: Psalms 54:1; Proverbs 18:10; 1Samuel 17:45.
**It is assumed that the person who submits to baptism has turned from sin to embrace Christ fully, which describes repentance. Hence, while baptism is the most conspicuous part of the Great Commission, it does refer to repentance (Luke 24:47) and receiving the Holy Ghost as well (John 20:22; Luke 24:49), which is why Peter preached what he did on the Day of Pentecost (Acts 2:38). Baptism appears dominant because it is an immediate act of faith, while receiving the promised Spirit may come later (e.g., Acts 8:12, 15-16). Oftentimes in the book of Acts, when no other feature of the plan of salvation is mentioned, baptism is (e,g., Acts 16:14-15; 31-33; 18:8). It is shorthand for conversion (Ephesians 4:5).