This concerns comparative Christian theology: the historical division of the early Christian church into three major branches — Roman Catholic, Eastern (Greek) Orthodox, and Protestant — following the ecclesial schism of 1054 and the Protestant Reformation, and the distinct doctrines of church authority, sacramental theology, and soteriology (theology of salvation) that differentiate them. Central theoretical constructs include the concept of the church as a teaching authority (with papal infallibility as its Catholic expression, conciliar authority as its Orthodox expression, and individual conscience as its Protestant expression), the sacramental system as a channel of divine grace, the Eastern emphasis on theosis (mystical union/deification), and the Protestant doctrines of justification by faith and the "Protestant principle" against absolutizing the relative. This belongs to the discipline of comparative religion and Christian theology, situating denominational variation as differing institutional and doctrinal responses to a shared foundational claim about Christ's teaching authority.
This concerns comparative Christian theology: the historical division of the early Christian church into three major branches — Roman Catholic, Eastern (Greek) Orthodox, and Protestant — following th…