question #1 Sahih Muslim 110a, Book 1, Hadith 208 : What are the consequences of taking an oath falsely in a religion other than Islam?

He who took an oath of a religion other than Islam, in the state of being a liar, would became so, as he professed. He who killed himself with a thing would be tormented on the Day of Resurrection with that very thing. One is not obliged to offer votive offering of a thing which is not in his possession.