15 While it is said, Today if you will hear his voice, do not harden your hearts, as in the rebellion.
Hebrews 3:15 Cross References - RKJNT
Hebrews 3:7-8
Hebrews 10:29
29 How much more severe punishment do you suppose he shall deserve, who has trodden under foot the Son of God, and has counted the blood of the covenant, with which he was sanctified, an unholy thing, and has affronted the Spirit of grace?
Hebrews 10:38
38 But my righteous one shall live by faith: but if any man draws back, my soul shall have no pleasure in him.