Marqus ibn Qunbar's Master and Disciple offers the critical edition and translation of a theological treatise that is published here for the first time. Marqus (+1208), a Coptic priest, was a controversial figure who challenged the Coptic hierarchs and eventually joined the Melkites. He argued that auricular confession is indispensible for salvation, but his superiors considered such teaching foreign to the Coptic heritage and incompatible with the Bible and Didascalia. For them, forgiveness is granted through repentance, the liturgy, and general absolution. The contentious disagreement sparked by Marqus among the Coptic community remains a subject of ongoing debate among Christians.