Know ye not, that so many of us as were baptized into Jesus Christ were baptized into his death?
Paul used the subject of baptism to show that it is morally unsuitable for believers to live in sin. When a person is saved, they identify with the death and resurrection of Christ. Baptism is the picture of that identification, a believer has died with Christ and has been raised with Him. The New Testament never contemplates the abnormal situation of an “unbaptized” believer. It assumes that those who are converted submit to baptism. Though baptism is not a requirement of salvation, it is a public sign of it.