pidyon ha-ben, Jewish ceremony in which the father redeems his wife’s firstborn son by offering to a cohen (a male Jew descended from the first priest, Aaron) the equivalent of five silver shekels (ancient coins). The ceremony, which normally takes place 30 days after the child’s birth, dates from Old Testament times, when the firstborn sons of the Israelites were spared from death on the first Passover (Exodus 12). These children subsequently belonged to God in a special way and would have constituted the Jewish priesthood had not the Levites been substituted in their place. Pidyon ha-ben thus commemorates a historical event, for the father ritually gives money to a cohen in order to keep his son. If the father is a cohen or if either parent is related to the tribe of Levi, such children already belong to God by reason of heredity, and no redemption is required.
In rabbinic law, the firstborn son may not actually have been the first, since the law does not apply to stillbirths, cesarean deliveries, and malformed offspring. Pidyon ha-ben also acknowledges the general law that, in the broadest sense, all “first fruits” (including grain, animals, and fruit) rightfully belong to God.