Why Born Again Christians Insist in Believer's Baptism by Immersion
I remembered a baptism chapel had a mural of Jesus being baptized by John the Baptist. However, biblical baptism has usually been by immersion. Even Roman Catholic translations of the Bible can't support infant baptism.
Consider these verses about baptism:
Matthew 3:17
As soon as Jesus was baptized, He came up out of the water. Then heaven was opened to him, and he saw the Spirit of God coming down like a dove and lighting on him. Then a voice said from heaven, This is my own dear Son, with whom I am pleased.
Acts 8:37-39
The official ordered the carriage to stop, and both Philip and the official went down into the water, and Philip baptized him. When they came up out of the water, the Spirit of the Lord took Philip away. The official did not see him again, but continued on his way, full of joy.
You can see that baptism in the Bible has always been by immersion. What is the other prerequisite? We need to get together with Peter whom Catholics consider as "the first Pope". What was written in Acts 2:38-41?
38 Peter said to them, “Each one of you must turn away from your sins and be baptized in the name of Jesus Christ, so that your sins will be forgiven; and you will receive God's gift, the Holy Spirit. 39 For God's promise was made to you and your children, and to all who are far away—all whom the Lord our God calls to himself.”
40 Peter made his appeal to them and with many other words he urged them, saying, “Save yourselves from the punishment coming on this wicked people!” 41 Many of them believed his message and were baptized, and about three thousand people were added to the group that day.
Once again, the requirement first is to repent before baptism. This repentance leads to believing in the Gospel message. When they believed then they were baptized. The same happened to the Ethiopian eunuch in Acts 8:37-39. In some manuscripts, Acts 8:37 in the footnotes has the confirmation of belief where the Ethiopian eunuch made his confession of faith. Before that, the Ethiopian eunuch was reading the Book of Isaiah before Philip baptized him. Acts 16 has Paul baptizing the household of the jailer that is after he preached the message to them.
The Greek word for baptism comes from baptizo (βαπτίζω) which literally means to submerge. Yes, that's why baptism for believers is immersion by default. The only exemptions can be in real special cases like a lack of water (which may be a good reason to postpone baptism) or if the one who got saved is currently incapacitated. Then again, baptism is not a prerequisite for salvation. If they can be baptized by immersion then there's no excuse not to do it.