Sayyiduna Thabit bin Dhahak (may Allah be pleased with him) narrates from the Noble Prophet (peace and blessings be upon him) that he said: "Whoever swears falsely by a religion other than Islam, for example, says, 'If such and such happened, then I am a Jew,' then he will be as he said. And whoever kills himself with a weapon, he will be punished in Hell with that same weapon."
Narrated by Sayyiduna Jundub (may Allah be pleased with him) from the Noble Prophet (peace and blessings of Allah be upon him) that he said: "A man received some wounds, so he killed himself. Allah the Exalted said: 'My servant has hastened before Me (i.e., he took his own life), therefore I have made Paradise forbidden for him.'"
Narrated Abu Huraira (may Allah be pleased with him): The Prophet (peace and blessings of Allah be upon him) said: "Whoever kills himself by throttling shall keep on throttling himself in the Hellfire, and whoever kills himself with a weapon shall keep on injuring himself with it in the Hellfire."