hardness of heart
7 Therefore, as the Holy Spirit says: "Today, if you will hear His voice, 8 Do not harden your hearts as in the rebellion, In the day of trial in the wilderness, 9 Where your fathers tested Me, tried Me, And saw My works forty years. 10 Therefore I was angry with that generation, And said, `They always go astray in their heart, And they have not known My ways.' 11 So I swore in My wrath, `They shall not enter My rest.' " 12 Beware, brethren, lest there be in any of you an evil heart of unbelief in departing from the living God; 13 but exhort one another daily, while it is called "Today," lest any of you be hardened through the deceitfulness of sin. 14 For we have become partakers of Christ if we hold the beginning of our confidence steadfast to the end, 15 while it is said: "Today, if you will hear His voice, Do not harden your hearts as in the rebellion."
18 the eyes of your understanding being enlightened; that you may know what is the hope of His calling, what are the riches of the glory of His inheritance in the saints,
30 And do not grieve the Holy Spirit of God, by whom you were sealed for the day of redemption.
1 Th. 4:8
8 Therefore he who rejects this does not reject man, but God, who has also given us His Holy Spirit.