Sunan an-Nasai Book 47, Hadith 5012

أَخْبَرَنَا أَبُو دَاوُدَ قَالَ حَدَّثَنَا جَعْفَرُ بْنُ عَوْنٍ قَالَ حَدَّثَنَا أَبُو عُمَيْسٍ عَنْ قَيْسِ بْنِ مُسْلِمٍ عَنْ طَارِقِ بْنِ شِهَابٍ قَالَ جَاءَ رَجُلٌ مِنْ الْيَهُودِ إِلَى عُمَرَ بْنِ الْخَطَّابِ فَقَالَ يَا أَمِيرَ الْمُؤْمِنِينَ آيَةٌ فِي كِتَابِكُمْ تَقْرَءُونَهَا لَوْ عَلَيْنَا مَعْشَرَ الْيَهُودِ نَزَلَتْ لَاتَّخَذْنَا ذَلِكَ الْيَوْمَ عِيدًا قَالَ أَيُّ آيَةٍ قَالَ الْيَوْمَ أَكْمَلْتُ لَكُمْ دِينَكُمْ وَأَتْمَمْتُ عَلَيْكُمْ نِعْمَتِي وَرَضِيتُ لَكُمْ الْإِسْلَامَ دِينًا فَقَالَ عُمَرُ إِنِّي لَأَعْلَمُ الْمَكَانَ الَّذِي نَزَلَتْ فِيهِ وَالْيَوْمَ الَّذِي نَزَلَتْ فِيهِ نَزَلَتْ عَلَى رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فِي عَرَفَاتٍ فِي يَوْمِ جُمُعَةٍ

It was narrated that Tariq bin Shihab said:"A Jewish man came to 'Umar bin Al-Khattab and said: 'O Commander of the Believers! There is a Verse in your Book which you recite; if it had been revealed to us Jews we would have taken that day as a festival.' He said: 'Which Verse is that?' He said: 'This day, I have perfected your religion for you, completed My favor upon you, and have chosen for you Islam as your religion.' 'Umar said: 'I know the place where it was revealed and the day on which it was revealed. It was revealed to the Messenger of Allah [SAW] at 'Arafat, on a Friday