Hebrews 3:8
do not harden your hearts as in the rebellion, on the day of testing in the wilderness,
Matthew 13:15
For this people's heart has grown dull. And their ears are hard of hearing, and their eyes they have closed, lest they should see with their eyes, and hear with their ears, and they understand with their hearts, and turn so that I should heal them.'
Acts 19:9
But when some were stubborn and disbelieved, speaking evil of the Way before the congregation, he withdrew from them, and took the disciples with him, reasoning daily in the hall of Tyrannus.
Romans 2:5-6
But by your hardness and your impenitent heart you are storing up wrath for yourself on the day of wrath when God's righteous judgment will be revealed.
1 Corinthians 10:9
We must not put the Lord to the test, as some of them did and were destroyed by serpents.
Hebrews 3:12-13
Take care, brethren, lest there be in any one of you an evil, unbelieving heart, leading you to fall away from the living God.