Imam Ja‘far al-Ṣadiq (as): There are seven grave sins: intentionally killing a believer, falsely accusing a chaste woman of fornication, fleeing from the midst of a battle, returning to a state of renegation after belief, unjustly usurping the property of the orphan, devouring usury after knowledge of its prohibition, and everything else that Allah has threatened to requite with obligatory punishment in the Fire. al-Kāfī