'Hard' in the Bible

And it shall happen on the day Yahweh gives you rest from your pain and turmoil and hard labor which {you had to perform},

And I will hand over {the Egyptians} into [the] hand of a hard master, and a powerful king will rule over them," {declares} the Lord Yahweh of hosts.

A hard revelation is told to me; the treacherous deals treacherously, and the destroyer destroys. Go up, Elam; lay siege, Media! I put an end to all of her sighing.

"O afflicted [one], driven away, [who] is not consoled. Look! I [am] about to set your stones in hard mortar, and I will lay your foundation with sapphires.