This verse clearly states that if you avoid committing major sins, God will forgive you your minor sins. This implies that sins are of two groups and grades according to the Islamic division: The first group of sins that QURÄN has classified them as the MAJOR ONES or the greatests of sins; and the second grades that are qualified as the MINOR SINS - (QURÄN S 18: 49) The major sins in the sight of Islam are the most heinous ones that give great offence. These are not only prohibited to do, but severe threats of punishment and joining the fire in Hell is followed when mention of them is made through the verses of Qurän. Instances of these heinous sins are; committing murder, usury and committing adultery, or devouring orphan's properties. On the other hand, small sins are counted as minor sin, provided they are not repeated and done frequently. If you ignore their effect and importance of being a sin, then you must expect their bad consequences.