The Teaching of Jacob, Didaskalia Jakobou; Ethiopic Sargis d'Aberga is a 7th century Greek Christian anti-Jewish polemical tract set in Carthage in 634 but written in Palestine sometime between 634 and 640. It supposedly records a July 13, 634 discussion between a Jewish forced convert to Christianity, Jacob, and some Jews about the condition of the Byzantine Empire in light of the recent Arab conquests, and how they should proceed as he had done, and convert to Christianity.
The text provides one of the earliest external accounts of Islam, presenting a significantly different Islamic historiography than found in traditional Islamic texts. It also shows Jacob comparing the Byzantine Empire to the fourth beast of the prophecy of Daniel from Christian eschatology. Although not unfamiliar imagery, it is part of a series of Byzantine literature, from the early stages of the Islamic religion, of trying to reconcile Islam with the apocalyptic vision. Further examples of this are contained in the pseudo-Athanasian's Quaestiones ad Antiochum ducem, and the Quaestiones et responsiones attributed to Anastasius of Sinai.
It records a prophet in Arabia during the birth time of Islamic tradition proclaiming the advent of a Jewish Messiah. The document contradicts the notion in Islamic tradition that the prophet was dead at the time of the conquest of Palestine but agrees with some traditions of other peoples of the time.