Sahih Bukhari

Narrated Tariq bin Shihab:The Jews said to `Umar, ""You (i.e. Muslims) recite a Verse, and had it been revealed to us, we would have taken the day of its revelation as a day of celebration."" `Umar said, ""I know very well when and where it was revealed, and where Allah's Messenger (ﷺ) was when it was revealed. (It was revealed on) the day of `Arafat (Hajj Day), and by Allah, I was at `Arafat"" Sufyan, a sub-narrator said: I am in doubt whether the Verse:-- ""This day I have perfected your religion for you."" was revealed on a Friday or not