Bite the hand that feeds.
[Idiom] BITE THE HAND THAT FEEDS. - Avoid Fatal Errors in Relationships: Learn from Idioms
Harm someone who helps you.
To "bite the hand that feeds" is to hurt or show ingratitude to someone who provides for you or helps you out. Imagine a dog biting the person feeding it—it symbolizes disloyalty or betrayal to those who are only trying to help.
Example Sentences
Don't bite the hand that feeds.
Don't act against those who support you.
Criticizing your manager might feel good, but remember not to bite the hand that feeds.
Criticizing your manager might feel good but remember not to act against those who support you.
Complaining about the company could hurt your job security, so don't bite the hand that feeds.
Criticizing your employer can jeopardize your job, so avoid acting against them.