'Observers' in the Bible

Then observers will say, "Yes indeed, the godly are rewarded! Yes indeed, there is a God who judges in the earth!"

"'This is what the sovereign Lord says: On the day it went down to Sheol I caused observers to lament. I covered it with the deep and held back its rivers; its plentiful water was restrained. I clothed Lebanon in black for it, and all the trees of the field wilted because of it.