SacrednessSacred describes something that is dedicated or set apart for the service or worship of a deity; is considered worthy of spiritual respect or devotion; or inspires awe or reverence among believers. The property is often ascribed to objects (a "sacred artifact" that is venerated and blessed), or places ("sacred ground"). French sociologist Émile Durkheim considered the dichotomy between the sacred and the profane to be the central characteristic of religion: "religion is a unified system of beliefs and practices relative to sacred things, that is to say, things set apart and forbidden.
SacramentA sacrament is a Christian rite that is recognized as being particularly important and significant. There are various views on the existence, number and meaning of such rites. Many Christians consider the sacraments to be a visible symbol of the reality of God, as well as a channel for God's grace. Many denominations, including the Catholic, Lutheran, Anglican, Methodist, and Reformed, hold to the definition of sacrament formulated by Augustine of Hippo: an outward sign of an inward grace, that has been instituted by Jesus Christ.
Full communionFull communion is a communion or relationship of full agreement among different Christian denominations or Christian individuals that share certain essential principles of Christian theology. Views vary among denominations on exactly what constitutes full communion, but typically when two or more denominations are in full communion it enables services and celebrations, such as the Eucharist, to be shared among congregants or clergy of any of them with the full approval of each.
HeresyHeresy is any belief or theory that is strongly at variance with established beliefs or customs, particularly the accepted beliefs or religious law of a religious organization. A heretic is a proponent of heresy. Heresy in Christianity, Judaism, and Islam has at times been met with censure ranging from excommunication to the death penalty. Heresy is distinct from apostasy, which is the explicit renunciation of one's religion, principles or cause; and from blasphemy, which is an impious utterance or action concerning God or sacred things.
Christian ChurchIn ecclesiology, the Christian Church is what different Christian denominations conceive of as being the true body of Christians or the original institution established by Jesus. "Christian Church" has also been used in academia as a synonym for Christianity, despite the fact that it is composed of multiple churches or denominations, many of which hold a doctrinal claim of being the "one true church", to the exclusion of the others.
Early ChristianityEarly Christianity, or Paleochristianity, describes the historical era of the Christian religion up to the First Council of Nicaea in 325. Christianity spread from the Levant, across the Roman Empire, and beyond. Originally, this progression was closely connected to already established Jewish centers in the Holy Land and the Jewish diaspora. The first followers of Christianity were Jews who had converted to the faith, i.e. Jewish Christians. Early Christianity contains the Apostolic age and is followed by, and substantially overlaps with, the Patristic era.
Church invisibleThe church invisible, invisible church, mystical church or church mystical, is a Christian theological concept of an "invisible" Christian Church of the elect who are known only to God, in contrast to the "visible church"—that is, the institutional body on earth which preaches the gospel and administers the sacraments. Every member of the invisible church is "saved", while the visible church contains all individuals who are saved though also having some who are "unsaved".
