Hebrews 4:10-12

10For he that is entered into his rest hath himself also rested from his works, as God did from his. 11Let us therefore give diligence to enter into that rest, that no man fall after the same example of disobedience. 12For the word of God is living, and active, and sharper than any two-edged sword, and piercing even to the dividing of soul and spirit, of both joints and marrow, and quick to discern the thoughts and intents of the heart.