Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
quran:85:3

And ˹by˺ the witness and what is witnessed,  

and ˹by˺ the witness, Friday, and the witnessed, the day of ‘Arafa — that is how these three ˹elements˺ have been explained in hadīth: for the first one is ‘promised’, the second one is ‘a witness’ ˹that testifies˺ to deeds performed in it, while the third is ‘witnessed’ by mankind and angels (the introductory ˹particle˺ of the response to the oath has been omitted, but is implied to be laqad, ‘verily’, ˹sc. laqad qutila ashābu’lukhdūd˺):
القرآن:٨٥:٣

وَشَاهِدٍ وَمَشْهُودٍ  

{وشاهد} يوم الجمعة {ومشهود} يوم عرفة كذا فسرت الثلاثة في الحديث فالأول موعود به والثاني شاهد بالعمل فيه، والثالث تشهده الناس والملائكة، وجواب القسم محذوف صدره، تقديره لقد.