There are two primary ordinances that the Church follows, Baptism and the Lord’s Supper. The reason they are called ordinances is because they were ordained by Jesus Christ, who is the head of the Church. Anything that Jesus ordains should be obeyed. Therefore, failure to do these two ordinances within a Church is disobedience.
This may lead to the question, “Did Jesus order the Church to baptize?” That question is easy. Yes. Matthew 28:19, “Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 20 teaching them to observe all that I have commanded you.” I have always found it odd that some churches want to make disciples, yet ignore the first act of obedience, baptizing the new follower of Christ.
Some people may argue that baptism is a spiritual act, not a physical act; therefore, physical baptism is not important. But that is not true. Yes, physical baptism points to a greater spiritual reality; however, make no mistake, Jesus desires an outward manifestation to proclaim an inward reality. Just a quick rundown to help demonstrate this: John the Baptist physically baptized, Jesus disciples physically baptized (John 4:1-2), the early Church physically baptized (Acts 2:38, Acts 8:36-38), the Church continued to physically baptized (1 Peter 3:21 written around 64 A.D.). So to throw out physical baptism is to throw out God’s Word and to disobey the clear teaching of Christ. Jesus wants an outward display of an inward reality.
This leads to a couple of questions, 1) Is baptism necessary? 2) What is the big deal about baptism?
Regarding whether baptism is necessary depends what you mean by necessary. Baptism is not necessary to be saved. Salvation comes through faith alone. The Bible is explicitly clear about this in numerous passages. Ephesians 2:8, “For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, 9 not a result of works, so that no one may boast.” If baptism was necessary for salvation, then that would be a result of work. The Bible tells us the only work that saves us is the work of Christ. Galatians 2:16, “yet we know that a person is not justified by works of the law but through faith in Jesus Christ, so we also have believed in Christ Jesus, in order to be justified by faith in Christ and not by works of the law, because by works of the law no one will be justified.”
Therefore, if you attend a so called church that tells you that baptism is necessary to be saved, then you go to a false, unbiblical, heretical Church and you should leave yesterday.
Having said that, baptism is necessary in the sense that Christ desires us to be physically baptized, and our heart should be to do what Christ desires. I always like the way John Frame describes baptism, it is the living word, in that baptism sends a message to ourselves and the world that we are dead to sin and alive in Christ.
And this leads us into answering the second question, what is the big deal? The big deal is that Christians exist to testify of Christ. This is why Christians remain in the world and are not taken to Heaven upon our conversion. We are to remain in the world and proclaim the realities of Jesus Christ. Baptism does just this. It proclaims the truth that Christ is our Savior King. Jesus, through the ordinance of baptism, immediately gives us the opportunity to participate in a ceremony that shares our faith with our family, our friends, our co-workers, and all those who see. It is the beginning of our life of evangelism, declaring that we are dead to sin and alive in Christ Jesus.