The New Testament is clear. Water baptism is a part of salvation. Those that say otherwise are not accepting the whole counsel of God and are actually cherry pickers.
Mark 16:16
He that believeth and is baptized shall be saved; but he that believeth not shall be damned.
Acts 2:37.38
Now when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do? Then Peter said unto them, 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.
1 Peter 3:21
The like figure whereunto even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God,) by the resurrection of Jesus Christ:
Colossians 2:11-13
In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ: Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead. And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses;
Romans 6:4
Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life.
I'm not saying one does not first repent, believe, and confess Jesus as their Lord and Savior. This is of course the first thing one does for initial salvation. Without doing this, one can get dunked in the water all they want and that does not make them saved. After initial salvation, the Lord instructs us to be baptized which is a public demonstration and public acknowledgement before others that we are dead with Him and are raised up together unto new life.... it is making a covenant with the Lord when we are baptized, making a commitment, making a promise to turn from our old life unto living for Him.
This process is the starting point for us to start walking in newness of life, having a clean conscience toward God which is what actually saves us. Being dunked in water itself is not the moment one becomes born again as we should already be born again before getting baptized. As mentioned in 1 Peter 3:21, having a clean conscience toward God having accepted Jesus as Lord and Savior, having confessed out sins before the Lord is what saves us. Now... as we see the thief on the Cross next to Jesus acknowledge the Lord as His Savior (Luke 23:39-43)... and Jesus told this man that he was going to paradise, if one finds themselves in a situation where it's not possible to get water baptized, then they will still be saved if they have truly been born again.
Apart from this, we are required to be baptized because God's tells us to be water baptized in His Word. Those having opportunity to be baptized and choose to disobey God's Word are disobeying the Gospel and the wrath of God comes upon the children of disobedience (knowingly disobeying the Lord is an evil desire, see Colossians 3:5,6).
Through the faith of the operation of God (Colossians 2:12) through water baptism are we raised up in newness of life (Romans 6:4) to have a clean conscience towards the Lord to walk with Him and we will be saved IF we endure until the end of our life abiding IN Christ.
Paul baptized a few folks (noted in 1 Corinthians 1:14-16) and did not teach water baptism was to be discontinued or ignored. Jesus answered and said to him, “Truly, truly, I say to you, unless one is born again he cannot see the kingdom of God.” Nicodemus said to Him, “How can a man be born when he is old? He cannot enter a second time into his mother’s womb and be born, can he?” Jesus answered, “Truly, truly, I say to you, unless one is born of water and the Spirit he cannot enter into the kingdom of God. That which is born of the flesh is flesh, and that which is born of the Spirit is spirit. (John 3:3-6)
The Lord teaches water baptism thru the Apostle Peter: Of Him all the prophets bear witness that through His name everyone who believes in Him receives forgiveness of sins.” While Peter was still speaking these words, the Holy Spirit fell upon all those who were listening to the message. All the circumcised believers who came with Peter were amazed, because the gift of the Holy Spirit had been poured out on the Gentiles also. For they were hearing them speaking with tongues and exalting God.
Then Peter answered, “Surely no one can refuse the water for these to be baptized who have received the Holy Spirit just as we did, can he?” And he ordered them to be baptized in the name of Jesus Christ. Then they asked him to stay on for a few days. (Acts 10:43-48) Some want to disobey the Lord claiming water baptism is not required so we'll see where these folks end up in eternity for ignoring the teachings of Jesus on this topic.
In conclusion, if one has opportunity to be baptized and chooses to ignore and disobey Mark 16:16, Acts 2:37.38, 1 Peter 3:21, Colossians 2:11-13, and Romans 6:4...then the after life is not going to be as they think.
