Our knowledge of Dositheus from patristic, Jewish and Arab sources is confused, contradictory and in some cases manifestly legendary. The practical impossibility of reconciling all the sources has led some authors given in McL. Wilson to postulate more than one person of this name. Given these difficulties, the facts must be treated with particular caution and accepted with reserve. Dositheus was a native of Samaria and lived probably in the 1st c. AD.
Hegesippus in Euseb., HE IV, 22,5 makes him the founder and leader of one of the seven heresies that disturbed the church’s peace as early as the 1st c. Ps.-Tertullian Adv. omnes haer. 1 puts him among the Jewish heretics, saying that he denied the inspiration of the prophets. The ps.- Clementines Hom. II, 24; Rec. I, 54; II, 8 connect him with John the Baptist and make him the predecessor and teacher of Simon Magus. Dositheus claimed to be Taeb, the Messiah of the Samaritans, and his disciples referred the prophecies of Dt 18:15 and Num 24:17 to him see Orig., C. Cels. 1,57; VI, 11; In Ioh. XIII, 27.
He was the author of various works that circulated among his followers. His teachings inspired the sect known as the Dositheans, whom we know, e.g., through the rather contradictory evidence of Epiphanius Pan. XIII and Eulogius of Alexandria 6th c.; in Photius, Bibl., cod. 230, and whom Arab sources document as still active in the 10th c. AD. On the doctrines of Dositheus and his sectaries our sources provide conflicting information, hard to organize into a single coherent picture.
In any case, from the available documentation it seems that Dositheus’s teachings were Encratite in character: great value was attributed to continence and virginity; in particular, he insisted on rigorous observance of the Mosaic Law, esp. regarding the Sabbath and prescriptions of ritual purity. One of the texts of the Coptic library of Nag Hammadi calls itself the Apocalypse of Dositheus Three Stelae of Seth NHC VII, 5: 118,10.
This reference to the obscure heresiarch of Samaria probably responds to the need to relate the work to someone traditionally linked with the origins of the gnostic movement, and may reflect the existence of relations between the so-called Sethian groups and the Samaritan tradition. According to Goulet, the heretic Dositheus of Cilicia, known only through the work of Macarius of Magnesia, should be distinguished from Dositheus of Samaria.