so help you (God)

so help you (God)

Used when introducing some hypothetical situation or outcome that would prove very problematic. She's a good teacher, and she's usually very pleasant. But so help you if you talk in the middle of her class. I'll let it slide for now, but so help you God if I find out you're lying to me.
See also: help
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
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