Hebrews 3:7, 13, 15
Hebrews 3:13 KJV
But exhort one another daily, while it is called To day; lest any of you be hardened through the deceitfulness of sin.
Hebrews 3:15 KJV
while it is said, To day if ye will hear his voice, harden not your hearts, as in the provocation.