In the lifetime of Allâh's Messenger (ﷺ) the (Prophet's) mosque was built of v adobes, its roof of the leaves of date-palms and its pillars of the stems of date-palms. Bakr did not alter it. Umarı expanded it on the same pattern as it was in the lifetime of Allâh's Messenger (ﷺ) by using adobes, leaves of date-palms and changing the pillars into wooden ones. ' Uthmân changed it by expanding it to a great extent and built its walls with engraved stones and lime and made its pillars of engraved stones and its roof of teak wood. [1:437-O.B.]