Hebrews 4:12 Indeed, the word of God is living and active, sharper than any two-edged sword, piercing until it divides soul from spirit, joints from marrow; it is able to judge the thoughts and intentions of the heart. 13 And before him no creature is hidden, but all are naked and laid bare to the eyes of the one to whom we must render an account.
We often think of the word of God as scripture – which it is. However, this passage understands the word of God in a way similar to John 1:1 “In the beginning was the word, and the word was with God, and the word was God.” In this sense the word (Greek “logos”) is the active presence of God that creates (as in Genesis). This is the word made flesh in Jesus. This is the word spoken over the waters of baptism that brings the baptized to new life.
As we read and study the written word of God, the logos of God is released to do a work in us. As the passage above indicates, there’s nothing hidden from the logos of God. That said, when the logos exposes the sin in our hearts he also drives us to repentance and forgiveness. Thanks be to God.