Dr. M.R. DeHaan put it this way:
In the early days of the church. . . , baptism was a declaration that the believer was definitely identifying himself with that group of people who were called Christians and were despised and hated. To be a Christian meant something. To identify yourself with those who were called Christians meant persecution, maybe death; it meant being ostracized from your family, shunned by friends. And the one act which was the final declaration of this identification was BAPTISM. As long as a man gathered with Christians, he was tolerated, but when once he submitted to baptism, he declared to all the world, I BELONG TO THEIS DESPISED GROUP, and immediately he was persecuted, hated, and despised. In baptism, therefore, the believer entered into
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