«زَيَّ ابُو قِرْدَانْ أَبْيَضْ وِعِفِشْ»

The saying mocks a person who looks clean and respectable but whose habits or nature are foul. The cattle egret's bright white feathers stand for an attractive outward show, while its worm-eating diet, the source of its uncleanness, stands for the hidden dirtiness that the appearance conceals.

The saying warns listeners not to trust surface impressions. A pleasing exterior can mask base behavior, so judging someone by looks alone invites disappointment. The irony sharpens the point: even a bird valued in the fields is called unclean once you notice what it actually eats.

Use it to criticize someone whose polished appearance, manners, or reputation hides unpleasant conduct or character. It is disparaging, not praise of the bird's usefulness. It suits informal talk among speakers who know the egret, and works as a pointed remark rather than a gentle joke.