I am not a particularly religious person. A doctrine that invites self-flagellation is not for me, who needs to find reasons to punish themselves? Not me. That being said, people like to punish themselves even if it is in a roundabout way. Some drink too much, some take drugs, others are risk takers, lovers of danger. There is also the punishment of avoidance, not doing things or taking an easier path. This is, perhaps, the most common self-punishment.