if you will hear his voice, don’t harden your hearts.
Hebrews 4 [6.] Seeing therefore it remains that some should enter therein, and they to whom the good news was before preached failed to enter in because of disobedience, he again defines a certain day, today, saying through David so long a time afterward (just as has been said),
“Today if you will hear his voice,
don’t harden your hearts.”[d]
Hebrews 4 [8.] For if Joshua had given them rest, he would not have spoken afterward of another day. There remains therefore a Sabbath rest for the people of God. For he who has entered into his rest has himself also rested from his works, as God did from his. Let us therefore give diligence to enter into that rest, lest anyone fall after the same example of disobedience. For the word of God is living and active, and sharper than any two-edged sword, piercing even to the dividing of soul and spirit, of both joints and marrow, and is able to discern the thoughts and intentions of the heart.
d. Hebrews 4:7 Psalm 95:7-8.