Scholars of genealogy know that their claimed lineage is false; that their forefather (1) was a Jew, inwardly as well as outwardly; and that another forefather of theirs was a Daysānī from among the Magians, who married this Jew’s wife. The Jew’s son was thus the stepson of a Magian and affiliated himself with his mother’s Magian husband. They also traced their affiliation to Bāhila, claiming to be among its clients. He himself claimed descent from Muhammad ibn Ismā'īl ibn Ja'far, to whom the Ismā'īlīs trace their affiliation. They claimed that the truth belonged exclusively to them rather than to the Twelvers, for the Twelvers assert the imamate of Mūsā ibn Ja'far, whereas these people assert the imamate of Ismā'īl ibn Ja'far.
The imams of these people are inwardly heretical unbelievers, worse than the extremist sects, and are not of the same kind as the Twelvers. Their sole route (2) to these corrupt doctrines and to attributing them to Alī was what the Twelvers and their like had done. Those people fabricated one kind of falsehood about him (3); these others developed it into further claims and added to it, until they ascribed heresy to him, just as they ascribed to him the doctrines of the Jahmiyya, the Qadariyya, and other such teachings.
Since these heretics—the Ismā'īlīs, the Nusayrīs, and their like—claimed affiliation (4) with Alī, and were Turuqiyya, Ashriyya, and Ghurabā, they and others like them began attributing to Alī things of which Allah had declared him innocent. It went so far that thieves among the Ashriyya claimed to possess a document from Alī authorizing them to steal people’s wealth, just as the Jews of Khaybar claimed to possess a document from Alī exempting them from the jizya,