The Messenger of Allah (blessings of Allah be upon him and his family) is reported to have said:
“The persons who secludes himself (in the Masjid in I’tikaf) in true faith and hope (for the reward of Allah), all of his previous sins shall be forgiven.” (Kanzul Ummal, Hadith 24007)
Hazrat Ayesha Radiallâhu anha relates that “Rasulullâh. Sallallâhu ‘alayhi wasallam regularly observed I’tikâf during the last ten days of Ramadhân till the end of his life. After him, his wives maintained the tradition.” (Bukhari)
It is related by Hazrat Abû Huraira Radiallâhu anhu that “Rasulullâh Sallallâhu ‘alayhi wasallam observed I’tikâf for ten days every year in the month of Ramadhân. In the year he passed away he observed it for twenty days.” (Bukhari)
3 TYPES OF ITIKAF
1. WAAJIB Itikaf.
This Itikaf becomes compulsory when a person makes it obligatory upon himself. An example of this is, when a person makes a vow to Allah that if Allah fulfills a certain wish of his, he will under take to perform so many days Itikaf. In this case the moment his wish is fulfilled, Itikaf becomes compulsory. A person may just make unconditional vow whereby he makes Itikaf Waajib upon himself for certain number of days. This becomes a Waajib duty on him from that moment onward.
2. SUNNAH Itikaf.
This was the general practice of Rasulullah (Sallallahu Alaihi Wasallam) and it means to seclude oneself inside the Masjid [for women at home]for the last ten days of Ramadhan.
3. NAFIL Itikaf.
There is no special time or specific number of days for Nafil Itikaf. A person may make niyyah for any number of days at any time, even for his whole life