. . . It judges the thoughts and the attitudes of the heart.
(Hebrews 4:12 NIV)
The Book of Hebrews warns us about the heart, the core of who we really are. We must not harden the heart (3:8), for it tends to stray (v. 10). Instead, God must write His law within our heart (8:10). We must draw near to God with a sincere heart (10:22), and we can do that only with a heart strengthened by His grace (13:9). God’s Word sifts, scrutinizes, and exposes the impulses and secret thoughts that belong to the emotional life, as well as the designs and purposes that belong to our rational, thinking life.