Fasting (Kitab Al-Siyam)

Dawud :: Book 13 : Hadith 2468

Narrated Abdullah ibn Umar:

Umar (may Allah be pleased with him) took a vow in the pre-Islamic days to spend a night or a day in devotion near the Ka'bah (in the sacred mosque). He asked the Prophet (peace_be_upon_him) about it. He said: Observe i'tikaf (i.e. spend a night or a day near the Ka'bah) and fast.