Recent studies of ancient compositional practices and the Synoptic Problem have validated the Two-Source hypothesis and challenged the “Augustinian,” Farrer–Goulder, and Griesbach hypotheses. These studies conclude that, according to the Two-Source hypothesis, subsequent evangelists would have adhered to the Greco-Roman conventions of working with one source at a time and not working backward through a text. The present essay adduces counterexamples such as the Greek Minor Prophets Scroll from Naḥal Ḥever, which predates the Gospels, and Tatian’s Diatessaron, which postdates the Gospels. Upon further examination, simultaneously accessing multiple sources and reordering those sources were established compositional practices in the first century. Moreover, every solution to the Synoptic Problem necessitates such scribal conventions. Therefore, the lesser extent of these ancient compositional practices does not privilege the Two-Source hypothesis over its rivals.