'Eye' in the Bible

All things toil continuously; no one can ever finish describing this. The eye is never satisfied with seeing, and the ear is never filled with hearing.

Sometimes a man is all alone with no companion; he also has neither son nor brother. Yet there is no end to all his toil, and his eye is not satisfied with wealth. [He laments,] "For whom am I toiling and depriving {myself} of pleasure?" This also [is] vanity--it is an unhappy business!