Sahih Bukhari Volume 5, Book 64, Hadith 4409

حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، حَدَّثَنَا سُفْيَانُ الثَّوْرِيُّ، عَنْ قَيْسِ بْنِ مُسْلِمٍ، عَنْ طَارِقِ بْنِ شِهَابٍ، أَنَّ أُنَاسًا، مِنَ الْيَهُودِ قَالُوا لَوْ نَزَلَتْ هَذِهِ الآيَةُ فِينَا لاَتَّخَذْنَا ذَلِكَ الْيَوْمَ عِيدًا‏.‏ فَقَالَ عُمَرُ أَيَّةُ آيَةٍ فَقَالُوا ‏{‏الْيَوْمَ أَكْمَلْتُ لَكُمْ دِينَكُمْ وَأَتْمَمْتُ عَلَيْكُمْ نِعْمَتِي‏}‏‏.‏ فَقَالَ عُمَرُ إِنِّي لأَعْلَمُ أَىَّ مَكَانٍ أُنْزِلَتْ، أُنْزِلَتْ وَرَسُولُ اللَّهِ صلى الله عليه وسلم وَاقِفٌ بِعَرَفَةَ‏.

Narrated By Tariq bin Shibab : Some Jews said, "Had this Verse been revealed to us, we would have taken that day as 'Id (festival)." 'Umar said, "What Verse?" They said: "This day I have Perfected your religion for you, Completed My Favour upon you And have chosen for you Islam as your religion" (5.3) 'Umar said, "I know the place where it was revealed; It was revealed while Allah's Apostle was staying at 'Arafat."