Is Itikaf restricted to the Two Holy Mosques and the Mosque of the Messenger of Allah, may Allah bless him and grant him peace?

According to the majority of scholars, it is not a condition for the validity of I'tikaf (spiritual retreat) that it be performed in the three holy mosques (Masjid al-Haram, al-Masjid an-Nabawi, and Bayt al-Maqdis). Rather, it is valid in the congregational mosque, which is preferred over others. The preponderant opinion is the permissibility of I'tikaf in any mosque where congregational prayers are held, based on the statement of Aisha (may Allah be pleased with her): "There is no I'tikaf except in a congregational mosque," and the generality of Allah's saying: "while you are secluded in the mosques" (2:187). Ibn Qudamah explained that I'tikaf is permissible in every mosque if the one performing I'tikaf is not obliged to attend congregational prayer, or if his I'tikaf is for a period that does not include a congregational prayer. The differing opinion of Hudhayfah (may Allah be pleased with him), who limited I'tikaf to the three mosques, is an ijtihad (independent reasoning) that was contradicted by Ibn Mas'ud and others, and it does not outweigh the general texts that permit I'tikaf in any mosque.