Chapter: The vow of a disbeliever, and what he should do about it if he becomes a muslim
Nafi' reported: A mention of Allah's Messenger ( صلی اللہ علیہ وسلم ) observing 'Umra from ja'rina was made before Ibn 'Umar. He said: He did not enter into the state of Ihram from that (place), and Umar had taken a vow of observing I'tikaf for a night during the days of Ignorance. The rest of the hadith is the same.
Authentic