"What did Allah's Apostle (peace be upon him) tell `Umar regarding his vow to perform I`tikaf in Al-Masjid-al-Haram?"
 Narrated Ibn `Umar:                     that `Umar had vowed in the Pre-Islamic period to perform I`tikaf in Al-Masjid-al-Haram. (A subnarrator thinks that `Umar vowed to perform I`tikaf for one night.) Allah's Apostle said to `Umar, "Fulfill your vow."