'Stiffened' in the Bible

Zedekiah rebelled against King Nebuchadnezzar, who had made him swear allegiance in the name of God. Instead, he stiffened his resolve, and hardened his heart, and would not return to the LORD God of Israel.

But they didn't listen to me, and they didn't pay attention. They stiffened their necks, and they did more evil than their ancestors.