This chapter explores two major anthropological ties: sharing food and contracting marriage in the Syrian-Orthodox church and the early Islamic community in the first Islamic century. To consolidate their authority over pagan and Christian Arabs, both early Syrian-Orthodox bishops and proto-Muslim authorities such as the readers of the Qurʾan (qurrāʾ) had to build religious communities. Miaphysite clerics attempted to separate those who were undoubtedly Christians from those who were uncertain. Banning interfaith social bonds among laypeople through canonical rulings proved to be the most effective legal method to confine them to their specific communal church. It seems that Muslim scholars also sought to delimit their own community (umma) by prohibiting their followers from engaging in the same social relations: through restrictions on food and marriage but not here relations with all Christians, as the Qurʾan permits these, but especially with the liminal category of “Christian Arabs.” To prevent the risk of diluting their umma, Muslim scholars, in turn, developed the same argument as Syriac scholars: that (Christian) Arabs were (crypto-)pagans.