The Messenger of Allah ﷺ said, "Whoever swears falsely by a religion other than Islam is as he has declared himself. Whoever kills himself with something in this world will be punished with it on the Day of Resurrection. And no man is bound by a vow concerning what he does not possess."
أخبرنا إسحق بن منصور قال حدثنا أبو المغيرة قال حدثنا الأوزاعي قال حدثني يحيى عن أبي قلابة
قال رسول الله ﷺ من حلف بملة سوى ملة الإسلام كاذبا فهو كما قال ومن قتل نفسه بشيء في الدنيا عذب به يوم القيامة وليس على رجل نذر فيما لا يملك
Reported by Bukhari in the Book of Manners, chapter "What Is Forbidden of Cursing and Insulting," h: 6047, and Muslim, the Book of Faith, chapter explaining the severity of the prohibition of a person killing himself, etc., h: 110, from the hadith of Yahya bin Abu Kathir, and it is found in Kubra, h: 4755.