The East-West Schism marked the division between the Roman and the Byzantine Church. Traditionally dated to 1054, the Schism was in fact a process that took considerable time. Nowadays, scholars tend to focus on one repertoire or the other, often neglecting the fact that the Eastern and Western Christian traditions shared more than a millennium of common history, and, indeed, their roots. In this paper, I introduce the early Christian musical traditions from the East and the West and show that these repertoires present similar methodological challenges. In addition, they can benefit from an approach that aims to explore, investigate, and reconnect those elements that now appear distant and separated.