The Messenger of Allah ﷺ said, "Whoever swears falsely and deliberately by a religion other than Islam is as he said." He also said, "Whoever kills himself with something, Allah will torment him with it in the Fire of Hell."
قال حدثنا عبد الرزاق حدثنا سفيان عن خالد الحذاء عن أبي قلابة
قال رسول الله ﷺ من حلف بملة سوى الإسلام كاذبا متعمدا فهو كما قال وقال من قتل نفسه بشيء عذبه الله به في نار جهنم
Its isnad is sahih, its narrators are leading authorities. Bukhari related the hadith 8/166, Shab edition, in the Book of Funerals, chapter on what has been said about one who kills himself, Muslim 1/105, no. 110, Tirmidhi 4/115, no. 1543, and Nasai 7/5/3770.