Hazrat Abu Hurayrah (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: "Avoid the seven destructive sins." They said: "O Messenger of Allah! What are they?" He (peace and blessings be upon him) said: "Associating partners with Allah, magic, killing a soul which Allah has made sacred except by right, consuming usury (riba), consuming the wealth of an orphan, fleeing from the battlefield on the day of fighting, and slandering chaste believing women."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوصايا / 12667