'Heavy' in the Bible

let the service be heavy on the men, and let them work at it, and not be dazzled by lying words.'

And the hands of Moses are heavy, and they take a stone, and set it under him, and he sitteth on it: and Aaron and Hur have taken hold on his hands, on this side one, and on that one, and his hands are stedfast till the going in of the sun;

thou dost surely wear away, both thou, and this people which is with thee, for the thing is too heavy for thee, thou art not able to do it by thyself.

And it cometh to pass, on the third day, while it is morning, that there are voices, and lightnings, and a heavy cloud, on the mount, and the sound of a trumpet very strong; and all the people who are in the camp do tremble.