let sleeping dogs lie
Definition from Wiktionary, the free dictionary
Template:The expression "let sleeping dogs lie" was a popular proverb by the 13th century. It alluded to the fact that waking "sleeping dogs" who were at the time trained to be fierce watchdogs, would cause nothing but trouble.
- (idiomatic) To leave things as they are; especially, to avoid restarting or rekindling an old argument; to leave disagreements in the past.
- Eventually, they decided it would be best to let sleeping dogs lie and not discuss the matter any further.
leave things as they are