This is question I ponder amongst Protestant who claim that baptism is not necessary for their salvation, how can they justify these Bible verses since they believe that believing is only necessary.
He who believes and is baptised will be saved" (Mark 16:16).
“Go therefore and make disciples of all nations, baptising them in the name of the Father and of the Son and of the Holy Spirit…” (Matthew 28:19).
“Truly. truly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God” (John 3:5)
Truly these verse support the necessary for salvation for all Christians.