Sahih Al-Bukhari Vol. 8 No. 73 Narrated by Thabit bin Ad Dahhak (raa): Allah’s Messenger (saws) said, “Whoever swears by a religion other than Islam (i.e. if somebody swears by saying that he is a non-Muslim e.g., a Jew or a Christian, etc.) in case he is telling a lie, he is really so if his oath is false, and a person is not bound to fulfill a vow about a thing which he does not possess. And if somebody commits suicide with anything in this world, he will be tortured with that very thing on the Day of Resurrection. And if somebody curses a believer, then his sin will be as if he murdered him. And whoever accuses a believer of Kufr (disbelief), then it is as if he killed him.”