Sahih al-Bukhari Book 33, Hadith 20
Allah's Messenger (ﷺ) mentioned that he would practice I`tikaf in the last ten days of Ramadan. `Aisha asked
his permission to perform I`tikaf and he permitted her. Hafsa asked `Aisha to take his permission for
her, and she did so. When Zainab bint Jahsh saw that, she ordered a tent to be pitched for her and it
was pitched for her. Allah's Messenger (ﷺ) used to proceed to his tent after the prayer. So, he saw the tents
ans asked, "What is this?" He was told that those were the tents of Aisha, Hafsa, and Zainab. Allah's
Apostle said, "Is it righteousness which they intended by doing so? I am not going to perform I`tikaf."
So he returned home. When the fasting month was over, he performed Itikar for ten days in the month
of Shawwal.
The Prophet (ﷺ) used to perform I`tikaf every year in the month of Ramadan for ten days, and when it was the year of his death, he stayed in I`tikaf for twenty days.
Aisha during her menses used to comb and oil the hair of the Prophet (ﷺ) while he used to be in I`tikaf in the mosque. He would stretch out his head towards her while she was in her chamber.