Tafsir of Al-Muddathir 74:47

And we used to deny the Day of Recompense, until the certainty (Al-Yaqin) came to us. meaning, death. This is as Allah says,

واعبد ربك حتى يٲتيك اليقين

and worship your Lord until there comes unto you the certainty. (15:99) The Messenger of Allah said,

أما هو يعني عثمان بن مظعون فقد جاءه اليقين من ربه

Concerning him verily, Al-Yaqin (death) came to him from his Lord.'' Allah then says,

فما تنفعهم شفاعة الشافعين