While a muʿtakif is fasting – i.e. from the time of ṣubḥ prayers until the time of maghrib prayers – everything that invalidates (i.e. makes bāṭil) a fast also invalidates iʿtikāf. Therefore, a muʿtakif must refrain from intentionally (ʿamdan) doing the things that invalidate a fast.[2] vi. Iʿtikāf must be performed in one of ‘the four mosques’ or a jāmiʿ mosque.