'Hard hearted' in the Bible

And thereto he rebelled against Nebuchadnezzar which had received an oath of him by God, and was too stiff necked and too hard hearted to turn unto the LORD God of Israel.

When divers waxed hard hearted, and believed not, but spake evil of the way of the Lord, and that before the multitude: he departed from them; And separated the disciples away; And disputed daily in the school of one called Tyrannus.

So hath he mercy on whom he will. And whom he will, he maketh hard hearted.

but exhort one another daily, while it is called today, lest any of you wax hard hearted through the deceitfulness of sin.

Again he appointeth in David a certain present day after so long a time, saying as it is rehearsed, "This day if ye hear his voice, be not hard hearted."