There is a difference between an Athiest and an Agnostic. An Agnostic is someone who is not sure if there is a God or not and even if there is, that God does not have a form or name or any human quality like anger and revenge. The Agnostic version of God does not punish someone if he or she commits a sin. But then they are not fully convinced that there is one, They are sceptics.. On the other hand, Athiests are fully convinced that there is no God, no life after death, no torment of the grave, no hell or heaven.. They believe, once you die, you just cease to exist..