The French saying “cracher dans la soupe” literally translates as “to spit in the soup.” What it really means is “to show contempt for something that benefits you” or “to criticise that which enables you to survive.”

The origin of this saying is unknown.

Its meaning, however, is quite clear. To spit in one’s own soup is a self-defeating act. Similarly, to act badly towards someone or something that helps or benefits you is equally self-defeating. One should not have contempt for something that benefits oneself.

The equivalent English expression is “to bite that hand that feeds you.”