Chapter 57: The Book of Commentary on the Qur'an
Tariq b. Shihab reported that a Jew said to 'Umar: If this verse were revealed in relation to the Jews (i e. "This day I have perfected your religion for you and have completed My favours for you and have chosen for you al-Islam as religion") we would have taken the day of rejoicing on which this verse was revealed. Thereupon 'Umar said: I know the day on which it was revealed and the hour when it was revealed and where Allah' s Messenger (ﷺ) had been when it was revealed. It was revealed on the night of Friday and we were in 'Arafat with Allah' s Messenger (ﷺ) at that time.
Sahih Muslim 3017b