'Harden' in the Bible
And the Lord said to Moses, When you return into Egypt, see that you do before Pharaoh all those miracles and wonders which I have put in your hand; but I will make him stubborn and harden his heart, so that he will not let the people go.
I will harden (make stubborn, strong) Pharaoh's heart, that he will pursue them, and I will gain honor and glory over Pharaoh and all his host, and the Egyptians shall know that I am the Lord. And they did so.
And I, behold, I will harden (make stubborn and strong) the hearts of the Egyptians, and they shall go [into the sea] after them; and I will gain honor over Pharaoh and all his host, his chariots, and horsemen.
If there is among you a poor man, one of your kinsmen in any of the towns of your land which the Lord your God gives you, you shall not harden your [minds and] hearts or close your hands to your poor brother;
For it was of the Lord to harden their hearts that they should come against Israel in battle, that [Israel] might destroy them utterly, and that without favor and mercy, as the Lord commanded Moses.
Why then do you harden your hearts as the Egyptians and Pharaoh hardened their hearts? When He had done wonders and made a mock of them, did they not let the people go, and they departed?
These ten times you have reproached me; you are not ashamed that you make yourselves strange [harden yourselves against me and deal severely with me].
Harden not your hearts as at Meribah and as at Massah in the day of temptation in the wilderness,
Fear not [there is nothing to fear], for I am with you; do not look around you in terror and be dismayed, for I am your God. I will strengthen and harden you to difficulties, yes, I will help you; yes, I will hold you up and retain you with My [victorious] right hand of rightness and justice.
Do not harden your hearts, as [happened] in the rebellion [of Israel] and their provocation and embitterment [of Me] in the day of testing in the wilderness,
Then while it is [still] called Today, if you would hear His voice and when you hear it, do not harden your hearts as in the rebellion [in the desert, when the people provoked and irritated and embittered God against them].
Again He sets a definite day, [a new] Today, [and gives another opportunity of securing that rest] saying through David after so long a time in the words already quoted, Today, if you would hear His voice and when you hear it, do not harden your hearts.