In the words of St. Jerome:
"Ignorance of the Scriptures is ignorance of Christ."
It was by the apostolic Tradition that the Church discerned which writings are to be included in the list of the sacred books. This complete list is called the canon of Scripture. It includes 46 books from the Old Testament and 27 for the New. The books of the Old Testament bear witness to the whole divine teaching of God's saving love: these writings "are a storehouse of sublime teaching on God and of sound wisdom on human life, as well as a wonderful treasury of prayers; in them, too, the mystery of our salvation is present in a hidden way."
In the writings of the New Testament the ultimate truth of God's Revelation is in Jesus Christ, God's incarnate Son: his acts, teachings, Passion and glorification, and his Church's beginnings under the Spirit's guidance. The Gospels are the heart of all the Scriptures "because they are our principal source for the life and teachings of the Incarnate Word, our Savior"
(Dei Verbum: Second Vatican Council I)
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