Jami` at-Tirmidhi, Volume 5, Book 44, Hadith 3043 (DarusSalam)

Narrated Tariq bin Shihab: "A man among the Jews said to 'Umar bin Al-Khattab: 'O Commander of the Believers! If we were the ones unto whom this Ayah was revealed, 'This day, I have perfected your religion for you, completed My favor upon you, and have chosen for you Islam as your religion (5:3).' - then we would have taken that day as a day of celebration.' So 'Umar bin Al-Khattab said to him: 'Indeed I do know which day this Ayah was revealed upon. It was revealed on the Day of 'Arafah, on Friday.'"

حَدَّثَنَا ابْنُ أَبِي عُمَرَ، حَدَّثَنَا سُفْيَانُ، عَنْ مِسْعَرٍ، وَغَيْرِهِ، عَنْ قَيْسِ بْنِ مُسْلِمٍ، عَنْ طَارِقِ بْنِ شِهَابٍ، قَالَ قَالَ رَجُلٌ مِنَ الْيَهُودِ لِعُمَرَ بْنِ الْخَطَّابِ يَا أَمِيرَ الْمُؤْمِنِينَ لَوْ عَلَيْنَا أُنْزِلَتْ هَذِهِ الآيَةُ ‏:‏ ‏(‏ الْيَوْمَ أَكْمَلْتُ لَكُمْ دِينَكُمْ وَأَتْمَمْتُ عَلَيْكُمْ نِعْمَتِي وَرَضِيتُ لَكُمُ الإِسْلاَمَ دِينًا ‏)‏ لاَتَّخَذْنَا ذَلِكَ الْيَوْمَ عِيدًا ‏.‏ فَقَالَ لَهُ عُمَرُ بْنُ الْخَطَّابِ إِنِّي أَعْلَمُ أَىَّ يَوْمٍ أُنْزِلَتْ هَذِهِ الآيَةُ أُنْزِلَتْ يَوْمَ عَرَفَةَ فِي يَوْمِ جُمُعَةٍ ‏.‏ قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ ‏.‏

sunnah.com