The Prophet (may Allah's peace and blessings be upon him) used to observe I‘tikāf [spiritual retirement in the mosque] during each Ramadan for ten days. The year in which he died, he observed I‘tikāf for twenty days. O Messenger of Allah, I had vowed, before embracing Islam, to make I‘tikāf for one night – another narration reads: for one day – the Sacred Mosque. He said: Then fulfill your vow. Whoever was in I‘tikāf with me should stay in I‘tikāf the last ten; for I was informed of that night, but I was then made to forget it. I saw myself prostrating in water and mud in its morning. So, seek it in the last ten The devil circulates in the son of Adam like blood. I feared lest he should cast evil thoughts in your hearts The Prophet (may Allah's peace and blessings be upon him) used to practice I‘tikāf (seclusion for worship) during the last ten of Ramadan until he died. Then his wives observed I‘tikāf after him