`ompulsory duties set by Allaah.” Authenticated in Saheeh Sunan at-Tirmithee, vol. 2, p. 133, no. 1363. For example, the darkened skin on the forehead from prostration during prayer or the darkened skin on parts of the feet from sitting on them in prayer. (“a mark received in Allaah’s path” for example, a wound or callous during fighting for the sake of Allaah.)