Q. What is the Word of God?
A. The holy Scriptures of the Old and New Testament are the Word of God (2 Tim. 3:16; 2 Pet. 1:19–21), the only rule of faith and obedience (Eph. 2:20; Rev. 22:18–19; Isa. 8:20; Luke 16:19, 21; Gal. 1:8–9; 2 Tim 3:15–16).
Chapter I: Of Holy Scripture
III. The books commonly called Apocrypha, not being of divine inspiration, are no part of the canon of the Scripture, and therefore are of no authority in the Church of God, nor to be any otherwise approved, or made use of, than other human writings.
For more on the subject, please visit the Systematic Theology page.