We’ve all heard it.

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In the South, ‘bless your heart’ situations arise all day, every day. Walk around long enough, and you’ll hear ‘bless your/their/his/her heart’ spoken either vehemently aloud or in a breathless whisper. It’s a versatile phrase indeed. It has a thousand meanings—and just as many possible responses.

If you’re on the receiving end of a ‘bless your heart,’ it might make you laugh...or it might sting a little. It’s usually good-natured, but you’ll have to listen closely, because ‘bless your heart’ has too many meanings to count. Southerners know that the meaning of the phrase depends on the tone in which it’s spoken, and a slight change in inflection or volume can make all the difference.

Stumped? Don’t know how to respond? Consider a few variables. Who’s speaking? What prompted the ‘bless your heart’? You can bet your Southern mamas, aunts, and grandmas are all well versed in the language of ‘bless your heart.’ In fact, they practically wrote the book, so you should study up too. Read on for Bless Your Heart 101, a few variants, and their appropriate responses.

Bless His/Her Heart

A conspiratorial ‘bless his/her heart’ is often spoken in a whisper. It’s not spoken to the proverbial blessed heart. It’s spoken to a friend or neighbor about the blessed heart. Usually, if the phrase is uttered to you in conversation about someone not present—or present, but out of earshot—the appropriate response is a smile, and perhaps a chuckle if you agree.

Bless Your Heart (Tone: Empathetic)

Everyone appreciates this version of ‘bless your heart,’ because it’s always kind and courteous. If ‘bless your heart’ is deployed in an expression of empathy or concern, a clear “Thank you, ma’am,” or “Thank you, sir” is appropriate. ‘Bless your heart’ said in this way is an outstretched hand, a pat on the back, an olive branch of understanding.

Bless Your Heart (Tone: Sassy)

If you’re not hearing sympathy, you’re most likely hearing a touch of sass (or, ok, more than a touch). Receiving this ‘bless your heart’ is a Southern rite of passage. There’s some judgment in this one, but you know it’s only because the person speaking has your best interests at heart. You may be tempted to respond with a return volley of salt or sass, but the best option is to smile and change the subject. (Unless, of course, you have a well-timed response teed up. If so—and if you have no fear of consequences—then the choice is yours.)

Bless My Heart

‘Bless my heart’ has a bevy of meanings, from self-sympathy to self-admonishment to self-deprecation to modesty. The appropriate response to ‘bless my heart’ is usually a sympathetic nod of the head. Not too emphatic (because that can be misinterpreted), but just enough to show that you understand or agree. If you're so moved, you can also offer a validating or concerned ‘bless your heart’ in return. Just watch your tone—it’s a powerful thing.

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When was the last time you heard ‘bless your heart’? How do you respond to this classic Southern saying? It's a true expression of Southern versatility, if we do say so ourselves.