God speaks through His word to the world. Here are different areas of scripture that confirm this Biblical Truth.
All words written in the bible are sufficient, God breathed. (John 10:27, 2 Tim 3:16)
God’s Word is the standard of Truth (John 17:17, Titus 1:2)
God’s Word is without error (Psalm 12:6)
The Word of God is the final Authority (1 Cor. 14:37)