The Catechism on Sacred Scripture - Sections 124 & 125

The New Testament
 
124 "The Word of God, which is the power of God for salvation to everyone who has faith, is set forth and displays its power in a most wonderful way in the writings of the New Testament"⁹⁶ which hand on the ultimate truth of God's Revelation. Their central object is Jesus Christ, God's incarnate Son: his acts, teachings, Passion and glorification, and his Church's beginnings under the Spirit's guidance.⁹⁷
 
125 The Gospels are the heart of all the Scriptures "because they are our principal source for the life and teaching of the Incarnate Word, our Savior".⁹⁸

96 DV 17; cf. Rom 1:16.
97 Cf. DV 20.
98 DV 18.

Source: Catechism of the Catholic Church