Mind your own business

To not interfere in someone else's affairs; to not pry or be nosy. Often used as an imperative. Mind your own business, will you? I can take care of my problems just fine. I really wish she would mind her own business and stop asking me about my finances. So there I was, minding my own business, when the security guard comes over and starts asking me all kinds of questions.

Fig. Stop prying into my affairs. (Not at all polite. The expressions with get and keep can have the literal meanings of removing and keeping removed.) Andy: This is none of your affair. Mind your own business. Sue: I was only trying to help. Bob: How much did you pay in federal taxes last year? Jane: Good grief, Bob! Keep your nose out of my business! Tom: How much did it cost? Sue: Tom! Get your nose out of my business! "Hey!" shrieked Sally, jerking the checkbook out of Sue's grasp. "Get your nose out of my business!"

To refrain from meddling, to keep to one’s own affairs. The wisdom of this course of action was observed in ancient times by Plato, Seneca, and others, and even found expression in the Bible (1 Thessalonians 4:11, “Do your own business”). In plain English it was expressed from the sixteenth century on. John Clarke used it in Paroemiologia (1639): “Mind your business.” Among many later writers echoing this sentiment was Lewis Carroll, in one of his enjoyable non sequiturs (Alice’s Adventures in Wonderland, 1865), “‘If everybody minded their business,’ the Duchess said in a hoarse growl, ‘the world would go round a great deal faster than it does.’”