18. Why does Sacred Scripture teach the truth?
Because God himself is the author of Sacred Scripture. For this reason it is said to be inspired and to teach without error those truths which are necessary for our salvation. The Holy Spirit inspired the human authors who wrote what he wanted to teach us. The Christian faith, however, is not a “religion of the Book”, but of the Word of God – “not a written and mute word, but incarnate and living” (Saint Bernard of Clairvaux).
Further reading: CCC 105-108, 135-13619. How is Sacred Scripture to be read?
Sacred Scripture must be read and interpreted with the help of the Holy Spirit and under the guidance of the Magisterium of the Church according to three criteria: 1) it must be read with attention to the content and unity of the whole of Scripture; 2) it must be read within the living Tradition of the Church; 3) it must be read with attention to the analogy of faith, that is, the inner harmony which exists among the truths of the faith themselves.
Further reading: CCC 109-119, 137