Most of the events he had foretold did in fact occur, and the turmoil among the people because of him swelled to the point that—they being hard-hearted, rough-natured, and quick to shed blood—they even killed their own sons and brothers. He therefore dispatched an army, saying: “Set out against these renegades who have tampered with the religion. Invite them to extinguish wrong, eliminate bidʿa (unwarranted innovation), and affirm the infallible Mahdi. If they comply, they are your brothers; if they refuse, the Sunnah has already allowed you to fight them.”
ʿAbd al-Muʾmin marched with the force toward Marrakesh. Al-Zubayr, son of the Amir al-Muslimin, confronted them; they presented the call, but received the most offensive reply. The Masmuda were then routed and a great number of them were slain. When news reached Ibn Tumart he asked, “Did ʿAbd al-Muʾmin escape?”
“It was said, “Yes.”
He replied, “Not a single man is missing,” soothed them, and added, “Your dead are martyrs.”
The amir ʿAzīz relates in Akhbār al-Qayrawān: “Ibn Tumart called his companions al-Muwaḥḥidūn (the Unifiers) and labeled his opponents al-Mujassima (the Anthropomorphists). In the year 515 AH he became widely known, and the tribe of Hargha pledged allegiance to him as the Mahdi. The Veiled Ones (al-Mulaththamūn) attacked, but they were broken, the spoils were taken, morale soared, reinforcements from the tribes poured in, and the powerful tribe of Hintata was united under him.
“His followers show warmth, courtesy, and cheerful faces; they dress in short, inexpensive garments, and let no day pass without hunting, lance practice, or archery. Some mischief-makers remained among the tribes, so Ibn Tumart summoned the tribal elders, admonished them, and said, ‘Your religion will never be sound unless you forbid what is wrong. Seek out every trouble-maker and restrain him; if he will not desist, send me his name.’ They did so. He then threatened a second time, took the names that appeared repeatedly, set them apart, gathered the tribes—insisting that no one be absent—handed the list to al-Bashīr, who examined it and then had the men parade past, one by one: whoever found his name was sent to the left, and whoever did not was dispatched…"