I say, and with God's success: A woman performs i'tikaf in the mosque of her house; because it is the place for her prayers, and her waiting in it is realized. If she does not have a designated place for prayer in her house, it is not permissible for her to perform i'tikaf in her house. She is not allowed to leave the house in which she has performed a mandatory i'tikaf. If she performs i'tikaf in the congregation mosque, it is permissible but with a dislike (tanzih) for her. The mosque of her neighborhood is better for her than the grand mosque; for the Prophet (peace be upon him) when asked about the best prayer for a woman, he said: 'In the darkest place of her house' as mentioned in Sahih Ibn Khuzaymah 3: 96. And from Aisha (may Allah be pleased with her), she said: 'It was mentioned that the Messenger of Allah (peace be upon him) used to perform i'tikaf during the last ten days of Ramadan, so I asked him for permission and he granted it to me. Hafsa asked Aisha to ask for permission for her, and she did. When Zainab bint Jahsh saw the buildings, she ordered for her building to be constructed. When the Messenger of Allah (peace be upon him) prayed, he went to his building and saw the buildings and said: What is this? They said: This is the building of Aisha, Hafsa, and Zainab. He said: Righteousness is intended by this, I am not in i'tikaf, so he returned. When he broke his fast, he performed i'tikaf for ten days of Shawwal' as mentioned in Sunan Al-Nasa'i Al-Kubra 2: 259, and Sahih Ibn Khuzaymah 3: 345. If it was disliked for them to perform i'tikaf in the mosque while they used to go out to the congregation at that time, then it is more appropriate for them to be prevented in our time. See: Al-Wiqayah p. 245, Al-Tabyin 1: 351, Al-Mabsut 3: 119, and Bada'i Al-Sana'i 2: 113, and Allah knows best.