The lapwing— The word rendered lapwing, says Parkhurst, דוכיפת dukipat, is the upupa or houp, a most unclean and filthy bird. So the LXX εποψ, and the Vulgate upupa. See Bochart, vol. 3: p. 343-9.
Note: God's people must not be rapacious, nor allow themselves in any deeds of impurity or darkness: such are still forbidden things.