There are numerous religions followed by mankind and every religion has concept of sin in it. Judaism is one of the ancient religions having concept of sin defined as disobedience of God. Islam also puts light on sin having the same meaning as in Judaism. This article describes sin and its categories in both the religions in major and minor sins. In Judaism sin is considered major while its punishment is death. On the contrary Islam’s description about major sins (the wrath of curses and curses of Allah or the strict promise of hell or punishment) includes a large number of sins in it. This discussion has resulted that although the punishments of sins are different from each other, yet both the religions have similar concept about it. The article has further elaborated these differences and that how a true follower of religion can become instrumental in reducing major social problems