bite the hand that feeds one

bite the hand that feeds (you)

To scorn or poorly treat those on whom you depend or derive benefit. You might not agree with your parents' rules, but be careful about biting the hand that feeds you, because you owe everything you have to them. In politics, if you bite the hand that feeds, benefactors can very quickly crush your political future.
See also: bite, feed, hand, that

bite the hand that feeds one

Fig. to do harm to someone who does good things for you. (Does not involve biting.) I'm your mother! How can you bite the hand that feeds you? She can hardly expect sympathy when she bites the hand that feeds her.
See also: bite, feed, hand, one, that