The belief that Jesus is the Christ has been fundamental to Christian faith down the ages. So basic a belief is it that it has become incorporated into essential Christian vocabulary. Already within the New Testament what is initially a Jewish title and role, 'the Christ/Messiah', as commonly in the gospels, becomes a proper name, Jesus Christ, as commonly in the letters of Paul and in Christian usage subsequently; and the followers of Jesus have been known as 'Christians' since earliest times (Acts 11.26).

It is a belief that can also be seen to encapsulate what came to be the Christian conviction that the Bible should be composed of two testaments, the scriptures of Israel in conjunction with the apostolic writings of the early church. For Christians the Bible contains both an Old Testament, where the Jewish category of ‘Christ/Messiah’ is formulated and becomes an important category for expressing hope in God’s action especially through the house of David, and a New Testament where Jesus fulfils and transforms Israel’s existing categories. Thus, major issues of biblical interpretation as a whole centre on the affirmation that Jesus is the Christ.