Scripture thus constitutes the Body of the Word. The ultimate meaning of the First Testament is revealed in Christ through symbols and a "typology" that reveals in the biblical characters and events "types," that is, images of the incarnate Word and its saving action. The domain of Christian symbolism is the Incarnation, the union of the Divine and the human in the person of the Word. Thus, the entire Bible is the moment of the Incarnation.

That's how you're to understand Scripture as the one and perfect Body of the Word.

Origen

Fragment of the homily on Jeremiah.

In the two angels [who appeared in Christ's tomb] we can recognize two Covenants... They met where the Lord's body is, for in a similar way announcing the Lord's incarnation, death, and resurrection, both Testaments seem to be there, the Old at His head, and the New at His feet. That is why the two cherubim guarding the atoning sacrifice also look at each other... In fact, the cherubim means the fullness of knowledge. What do the two cherubim symbolize if not the two Testaments? What is the sacrifice if not of the Incarnate Lord, of whom John says that He became a sacrifice for sin? When the Old Testament shows how that which the New Testament proclaims to be accomplished in the Lord, they look at each other like two cherubim, turning their gaze to the atoning sacrifice. according to the mystery ordained by His love.

Gregory the Great

Homilies on the Gospels, 2, 53, 3.

The presence of the Word is given in the circles of initiation: the closer it is, the more intense this presence is. The Bible is the "gospel preparation" and is concentrated in the Gospels, which in turn find their fullness in the Gospel of full consecration, the Gospel of John. To enter into John's proclamation is to identify with Christ's beloved disciple. Here the invocation of the Name is announced, in the rhythm of the beating of the heart of Jesus, on whose bosom rests the head of John.

The crucified Jesus, Mary and John on both sides of the cross: this is the first Church (not yet Peter's, but already John's) to which Jesus gives the Spirit of Svop (Luke 23:46) and the sacraments (John 19:34).