According to Tabari, based on traditions collected by Sayf ibn Umar, Ibn Saba' was a Yemenite Jew who embraced Islam. During the time of Ali ibn Abi Taleb, he introduced a number of concepts that later were ascribed to more extreme factions of Shia Islam, or ghulat. According to these traditions, the exaltation of Ali, his divine appointment by the Islamic prophet Muhammad as a successor, the concept of occultation (ghayba) and return (rajʿa) were first formulated and expressed by Ibn Sabaʾ and his followers (the Sabaʾiyya).Bibliography: Shatrastani al-Milal, pp. 132 et seq. (in Haarbrücken's translation, i. 200-201); Weil, Gesch. der Chalifen, i. 173-174, 209, 259. He and his followers are sometimes said to be the ones who enticed the Egyptians against Uthman on the ground of Ali's special right of succession, and participated in further instigation at later conflicts. Historically, Sunni theologians have not only upheld Ibn Saba's existence, but used evidence from the historical works of the Shi'a in order to support their claims.Zubair Ali Zai, Who was Abdullah Ibn Saba? Birmingham: Maktabah Imaam Badee ud Deen, 2011.
