Romans 2:5
The fact is that in the stubbornness of your impenitent heart you are treasuring up against yourself anger on the day of Anger--the day when the righteousness of God's judgements will stand revealed.
Hebrews 3:8-9
do not harden your hearts as your forefathers did in the time of the provocation on the day of the temptation in the Desert,
Hebrews 3:13
On the contrary encourage one another, day after day, so long as To-day lasts, so that not one of you may be hardened through the deceitful character of sin.
Hebrews 3:15-19
seeing that the warning still comes to us, "To-day, if you hear His voice, do not harden your hearts as your forefathers did in the time of the provocation."
Hebrews 12:25
Be careful not to refuse to listen to Him who is speaking to you. For if they of old did not escape unpunished when they refused to listen to him who spoke on earth, much less shall we escape who turn a deaf ear to Him who now speaks from Heaven.
Jude 1:5
I desire to remind you--although the whole matter is already familiar to you--that the Lord saved a people out of the land of Egypt, but afterwards destroyed those who had no faith.
Acts 19:9
But some grew obstinate in unbelief and spoke evil of the new faith before all the congregation. So Paul left them, and, taking with him those who were disciples, held discussions daily in Tyrannus's lecture-hall.