It is narrated from Sayyiduna Thabit bin al-Dahhak (may Allah be pleased with him), and he was a Companion, that he said: The Messenger of Allah (peace and blessings be upon him) said: "Whoever deliberately kills himself with something will be punished with it on the Day of Resurrection in the fire of Hell; and whoever deliberately swears falsely by a religion other than Islam, he is as he said; and whoever accuses a believer of disbelief, it is like killing him; and whoever curses a believer, it is like killing him."
Hadith Referenceالمعجم الكبير للطبراني / باب الثاء / 1316