Language can mirror relationships throughout and between communities, while it enables connections and separation simultaneously. Jewish and Christian communities had a close but complicated relationship in the late antique-early Islamic period in Babylon (the fertile crescent). That relationship included similar dialects of Aramaic: Jewish Babylonian Aramaic and Christian Syriac Aramaic. My study describes changes and developments in the status of an apostate (Heb. Meshumad) in the Jewish literature of late antiquity, by examining terminological variations. In this presentation, I wish to present the Syriac developments and to compare the two, in order to better conceptualize the mutual process in one terminological and conceptual case. One such case is the defining of the apostate, not only by his apparent wrong doing, but also by seeking his motivation to act. According to that model, if an evil act originated from his desire or lewdness, he should be judged in a more containing manner than if it had originated by rage or theological purpose. This was phrased in Hebrew by the words Meshumad le-Teavon ‘apostate out of desire.’ The second word le-Teavon (for (his) desire), is a predicate added to the basic ancient term Meshumad, ‘apostate.’ This model and new phrasing are connected mainly with Rava, who was a prominent sage who lived in 4th century CE in Mehoza, close to Ctesiphon, the capitol of the Persian Sassanian dynasty. The Syriac word Shmad is well attested, and more so since the early testimonies of Syriac literature, in different forms, connected to the semantic field of curse, ban, and excommunication. Only in sources from the 5-6th centuries CE do we find a new form of that root Meshamdotho, which suggests ‘lewdness,’ ‘to be wanton.’ The new form changes the focus of the root from describing the wrongdoing and its social implication to describing the manner of doing, maybe even to the motive for his or her behavior. My presentation will raise the question of the connection between those almost parallel changes. Are they related to one another? In what way? What is similar and what are the differences? Can we explain the reason for raising a new paradigm in communal defining the apostates and wrong doers? I will examine some sources, Jewish and Christian, that relate to those terms and ideas.