Hebrews 3:15
while it is said, "Today, if you will hear his voice, do not harden your hearts as in the rebellion."
Hebrews 3:7-8
Therefore, as the Holy Spirit says: "Today, if you will hear his voice,
Hebrews 10:29
How much severer punishment do you think a man will deserve who has trampled under foot the Son of God, and has regarded as an unclean thing the blood of the covenant by which he was sanctified, and has insulted the Spirit of grace?
Hebrews 10:38
But my righteous one shall live by faith, and if he shrinks back, my soul has no pleasure in him."
Treasury of Scripture Knowledge
Summary
While it is said, To day if ye will hear his voice, harden not your hearts, as in the provocation.