Abu Hurairah (May Allah be pleased with him) said:
The Prophet (SAW) said, "Avoid the seven destructive things." It was asked: (by those present): "What are they, O Messenger of Allah?" He replied, "Associating anyone or anything with Allah in worship; practising sorcery, killing of someone without a just cause whom Allah has forbidden, devouring the property of an orphan, eating of usury, fleeing from the battlefield and slandering chaste women who never even think of anything touching chastity and are good believers."
[Al-Bukhari and Muslim].