The Christian concept "Church" (Greek e????s?a — ekklesia, ref. Strong's Concordance — 1577) is mentioned in the New Testament. Of the 114 occurrences of the term in the New Testament, three are found in the Gospel accounts, all spoken by Jesus in the Gospel of Matthew: "And I tell you that you are Peter, and on this rock I will build my ekklesia, and the gates of Hades will not overcome it" (Mt 16:18); and "If he refuses to listen to them, tell it to the ekklesia; and if he refuses to listen even to the ekklesia, let him be to you as the Gentile and the tax-collector" (Mt 18:17).

The Greek term e????s?a — ekklesia, which literally means a "convocation", was a governmental and political term, used to denote a national assembly, congregation or council of common objective (see Ecclesia (ancient Athens), Ecclesia (Church)). It was a team that worked together to resolve a problem faced by the wider community or society, but did not signify a "building".

The Christian use of this term has its direct antecedent in the Koine Greek translation of the Old Testament (see also Septuagint), where the noun ekklesia has been employed 96 times to denote the congregation of the Children of Israel, which Christians regard as a type of the "Body of Christ", as they also call the Christian Church of Christ.

The history of Christianity concerns the history of the Christian religion and the Church, from Jesus and his Twelve Apostles to contemporary times. Christianity is the monotheistic religion which considers itself based on the revelation of Jesus Christ. "The Church" is understood theologically as the institution founded by Jesus for the salvation of mankind.

Christianity began in the 1st century AD as a Jewish sect but quickly spread throughout the Greco-Roman world. Although it was originally persecuted under the Roman empire, it would ultimately become the state religion. In the Middle Ages it spread beyond the old borders of the Empire into Northern Europe and Russia. During the Age of Exploration, Christianity expanded throughout the world; it is the world's largest religion.

Throughout its history, the religion weathered schisms and theological disputes that have resulted in the development of three main branches: the Roman Catholic Church, the Eastern Orthodox churches, and Protestant churches.