good thing you don't keep guns in the house
A phrase used in response to somebody overreacting over a minor or petty incident.
Bob: Those idiots at Taco Bell messed up my damn order again! I should go over there and slap some goddamn sense into those stupid shits!
Dave: Sheesh. Good thing you don't keep guns in the house.
Dave: Sheesh. Good thing you don't keep guns in the house.