عبيد الله بن جحش
Ubaydillah ibn Jahsh was a cousin of the Prophet ﷺ and one of the four hunafa' who sought the religion of Ibrahim AS before Islam, becoming a Christian. He accepted Islam, married Umm Habiba bint Abi Sufyan RA and emigrated with her to Abyssinia, where he returned to Christianity, perhaps the only Companion to apostatize, and soon died. The Prophet ﷺ then married his widow.
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