
The New Testament is the second part of the Christian biblical canon. The first part being the Old Testament, based on the Hebrew Bible. The New Testament discusses the teachings and person of Jesus, as well as events in first-century Christianity. Christians regard both the Old and New Testaments together as sacred scripture. The New Testament (in whole or in part) has frequently accompanied the spread of Christianity around the world. It reflects and serves as a source for Christian theology and morality.

The Old Testament (OT) is the first part of Christian Bibles. This is based primarily upon the Hebrew Bible (or Tanakh), a collection of ancient religious writings by the Israelites believed by most Christians and religious Jews to be the sacred Word of God. The second part of the Christian Bible is the New Testament.
The books that comprise the Old Testament canon, as well as their order and names, differ between Christian denominations. The Catholic canon comprises 46 books, and the canons of the Eastern Orthodox and Oriental Orthodox Churches comprise up to 51 books and the most common Protestant canon comprises 39 books.

The Christian doctrine of the Trinity (Latin: trinus "threefold") holds that God is one God, but three coeternal consubstantial persons or hypostases. These being the Father, the Son (Jesus Christ), and the Holy Spirit - as "one God in three Divine Persons". The three Persons are distinct, yet are one "substance, essence or nature" (homoousios).