1. First we need to attain a proper understanding of Baptism and what it is.
Proper Authority - The church was given the authority to Baptise Matthew 28:19
Proper Candidate - The proper candidate is the believer in Christ Acts 8:26-39
Proper Purpose - The proper purpose of baptism is to identify us with Christ and the church, not the remission of sins as many teach. Ephesians 2:8 states "not of works of righteousness", and baptism is classified as a work of righteousness, so therefore is not necessary for salvation.
Baptism identifies us with Christ Romans 6:4
The proper mode of baptism is full immersion. Greeks use the word baptizo to describe one ship sinking another.
2. Next we need to know who improper candidates for baptism are.
Those with impure hearts Acts 8:5-24
Those with an incomplete message. Acts 19:1-7
Those with insincere belief....
Nero made it a crime to be a Christian, Constantine the great made it a crime not to be a Christian. Therefore those people would believe for fear of persecution, rather than sincere belief in Jesus Christ.
3. Next we need to know that baptism is proper for obedience. Matthew 28:19
The Multitude as in Acts 2:41
A Eunuch as in Acts 8:36-38
A Jailer, as in Acts 16:23
The Basic two fold purpose of Baptism
It identifies us with Christ, and the local church.
See Romans 6:4, and Acts 2:41