To put your oar into my boat. To interfere with my affairs. “Paddle your own canoe, and don't put your oar into my boat.” “Bon homme, garde ta vache.” “Never scald your lips with another man's porridge”
(Scotch). “Croyez moi chacun son metier, et les vaches sont bien gardées.”
“I put my oar in no man's boat.” —Thackeray.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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