'Heavy' in the Bible

Behold, about this time tomorrow, I will send a very heavy hail, such as has not been seen in Egypt from the day it was founded until now.

But Moses’ hands were heavy. Then they took a stone and put it under him, and he sat on it; and Aaron and Hur supported his hands, one on one side and one on the other. Thus his hands were steady until the sun set.

You will surely wear out, both yourself and these people who are with you, for the task is too heavy for you; you cannot do it alone.