'Hard' in the Bible

Simon answered and said, “Master, we worked hard all night and caught nothing, but I will do as You say and let down the nets.”

But He said, “Woe to you lawyers as well! For you weigh men down with burdens hard to bear, while you yourselves will not even touch the burdens with one of your fingers.

And Jesus looked at him and said, “How hard it is for those who are wealthy to enter the kingdom of God!