The apologetical writings of the Jacobite Christian, Ab? R?'i?ah al-Takr?t? (+ c. 835) have remained relatively unknown in Western scholarship. Yet his engagement with Muslim questions about Christianity provides a significant insight into the theological debate between the two communities in the early ?Abb?sid period. Ab? R?'i?ah's treatises take up many of the topics that become standard for Christian-Muslim apologetics: proofs of the true religion, the Trinity, the Incarnation, and Christian practices. In each case, he provides his reader with complex arguments in defense of Christian doctrines that can be used to convince both Muslims and wavering Christians of the truth of Christianity. This new Arabic edition and English translation seeks to contextualize Ab? R?'i?ah's important writings and to make the original texts available to modern scholars interested in all aspects of the early development of Muslim-Christian relations.