let (something) pass
To ignore, refuse to acknowledge, or choose not to retaliate against something someone else says or does. Those comments are very hurtful, but I'm going to let them pass because I know how frustrated you are. You have to let people's criticisms pass if you want to succeed in this industry.
let something pass
Fig. to let something go unnoticed or unchallenged. Bob let Bill's insult pass because he didn't want to argue. Don't worry, I'll let this little incident pass.