'Hard' in the Bible

But by your hard and unchanged heart you are storing up wrath for yourself in the day of the revelation of God's judging in righteousness;

Now it is hard for anyone to give his life even for an upright man, though it might be that for a good man someone would give his life.

So then, at his pleasure he has mercy on a man, and at his pleasure he makes the heart hard.

What then? That which Israel was searching for he did not get, but those of the selection got it and the rest were made hard.

So I say, Were their steps made hard in order that they might have a fall? In no way: but by their fall salvation has come to the Gentiles, so that they might be moved to envy.

See then that God is good but his rules are fixed: to those who were put away he was hard, but to you he has been good, on the condition that you keep in his mercy; if not, you will be cut off as they were.

For it is my desire, brothers, that this secret may be clear to you, so that you may not have pride in your knowledge, that Israel has been made hard in part, till all the Gentiles have come in;

Then let us not be judges of one another any longer: but keep this in mind, that no man is to make it hard for his brother, or give him cause for doubting.

Do not let the work of God come to nothing on account of food. All things are certainly clean; but it is evil for that man who by taking food makes it hard for another.