What is Kumayl/Kumail dua?

[Flos]

Assalamu alaikum,

I just heard about this dua, but as I never heard about it before, what is it? Where it comes from? Is there anything wrong with it? Someone to explain please?

 

['Abdullah]

WaAlaikum Assalam WaRahmatullhi WaBarakatuhu Sister

This dua is famous among Shias, it is best not to follow the people of innovations & Allah knows the best. For details, please see article below:
https://islamqa.info/en/answers/181861/ruling-on-a-duaa-called-duaa-kumayl-ibn-ziyaad

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[TR][TD]Ruling on a du‘aa’ called “Du‘aa’ Kumayl ibn Ziyaad” - Islam Question & Answer
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[Flos]

WaAlaikum Assalam WaRahmatullhi WaBarakatuhu Sister

This dua is famous among Shias, it is best not to follow the people of innovations & Allah knows the best. For details, please see article below:
https://islamqa.info/en/answers/181861/ruling-on-a-duaa-called-duaa-kumayl-ibn-ziyaad

[TABLE="class: grid, width: 100%, align: center"]
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[TD]Ruling on a du‘aa’ called “Du‘aa’ Kumayl ibn Ziyaad” - Islam Question & Answer
...[/TD]
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Meaning of the dua is also strange. Part of it says something like "I swear if I'd be thrown to Jahannam I would call you hoping for your Mercy." How can anyone swear to do something in the Akhirah?