sink to somebody's level
sink to (someone's) level
To behave as badly, immorally, or basely as someone else, especially in a dispute or conflict. Don't hit him, Tom, just walk away; don't sink to his level. We'll have to sink to their level if we're going to stay competitive in the market.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
sink to somebody’s ˈlevelstop behaving well and begin to behave badly, especially in an argument or a fight, because other people are behaving in this way: Use words, not violence, or you’ll just be sinking to their level.
Farlex Partner Idioms Dictionary © Farlex 2017