The Acts of Thomas is a retelling of the events during the ministry of Judas Thomas in India, or Mar Tuma as he is known among Manichaeans. The Manichaean Church believes the Acts were composed during the time of Mar Tuma, but later re-adapted during the time of the Prophet Mar Mani.
It is believed to have originally been written in Syriac and later translated to Greek. According to one source, “The major Greek witnesses… date to the 11th century, although there are partial Greek witnesses dating from the 10th… Epiphanius (Anac. 47.1 and 60.1.5) records its use by Encratites. Augustine (de serm. dom. in monte 1.20.65; c. Adiamantium 17; c. Faustum 14 and 22.79) attests its use by Manicheans, and allusions are found in the Manichean Psalms. Attestations continue sporadically until the 9th-century Byzantine patriarch Photius (Cod. 114) and the 11th-century archbishop, Nicetas of Thessalonica, who paraphrased the work… It is likely that Acts Thom. underwent redactional development, including adaptation by Manicheans, in the late 3d or 4th centuries.” (The Anchor Bible Dictionary, Volume 6, page 531)
The New World Encyclopedia refers to the Acts of Thomas as “one of the New Testament apocrypha, describing the adventures and martyrdom of the Apostle Thomas, whom it portrays as Jesus’ twin brother… The work provides dramatic narratives of Thomas’ miraculous evangelistic adventures in India, where he traveled after being sold as a slave by the resurrected Jesus. It ends with Thomas’ martyrdom as a result of the enmity of the monarch Misdaeus… A lengthy and well constructed narrative, the Acts of Thomas is the most complete of several “Acts” relating to the Apostle Thomas, who plays a major role in Gnostic literature, while he is denigrated as “Doubting Thomas” in the canonical Gospels because he doubts Jesus’ physical resurrection. It should not be confused with the Gospel of Thomas, which deals with Jesus’ sayings in a Gnostic context, but contains almost no narrative elements.”
The Acts of Thomas is a canonical text of the Manichaean Holy Book.