In the south “Bless your heart” means are you really that STUPID!
I thought “Bless your heart”, means ‘Perform an anatomically impossible act on yourself!”
That's not necessarily true. "Bless your heart" can be endearing as well, but it depends on when it is said in the conversation referenced. Normally it depends on whether you say it at the beginning of a statement or after. For example:
Bless her heart he husband left her. That's empathetic.
He can't find his behind with both hands, bless his heart. This implies stupidity.
In the south Bless your heart means are you really that STUPID!
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Short for “Bless your pea picking heart”.