Baptism (Greek: baptein = immersion) is a term usually applied to the Christian ritual of initiation by water, and it is the psychology of this ritual that will be addressed here. It must be noted, however, that such acts are by no means peculiar to Christianity. In many other traditions of the ancient and modern world, water is used for ritual cleansing and/or initiation. Ritual washings at death can symbolize a cleansing in preparation for the journey to another world, as in the case of the ancient Egyptians. The Greeks had many bathing rites, as, for example, in the washing of initiates entering into the Eleusinian mysteries. Jews have ablution ceremonies associated with washing away various forms of uncleanliness. Muslims perform ritual ablutions before praying.
Baptism for Christians can be compared to Jewish circumcision in the sense that through baptism, the individual is “marked as Christ’s own forever” as in circumcision the Jew is marked as a part of his “nation” forever.