From Sahih Bukhari (Hadith 7268):
Narrated Tariq bin Shihab:A Jew said to `Umar, "O Chief of the Believers, if this verse: 'This day I have perfected your religion for you, completed My favors upon you, and have chosen for you, Islam as your religion.' (5.3) had been revealed upon us, we would have taken that day as an `Id (festival) day." `Umar said, "I know definitely on what day this Verse was revealed; it was revealed on the day of `Arafat, on a Friday
Reference: Bukhari 7268