'Labor' in the Bible

Behold, is it not of Jehovah of hosts that the peoples labor for the fire, and the nations weary themselves for vanity?

For though the fig-tree shall not flourish, Neither shall fruit be in the vines; The labor of the olive shall fail, And the fields shall yield no food; The flock shall be cut off from the fold, And there shall be no herd in the stalls: