(47) The Book Of Faith and its Signs
كتاب الإيمان وشرائعه
(7) Chapter: Interpreting the Saying of Allah, The Mighty and Sublime: "The Bedouins say: We believe,
Sunan an-Nasa'i 4994 
It was narrated from Bishr bin Suhaim that:
The Prophet [SAW] commanded him to call out on the days of At-Tashriq that no one would enter Paradise except a believer, and that these were the days of eating and drinking.
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا حَمَّادٌ، عَنْ عَمْرٍو، عَنْ نَافِعِ بْنِ جُبَيْرِ بْنِ مُطْعِمٍ، عَنْ بِشْرِ بْنِ سُحَيْمٍ، أَنَّ النَّبِيَّ صلى الله عليه وسلم أَمَرَهُ أَنْ يُنَادِيَ أَيَّامَ التَّشْرِيقِ ‏ "‏ أَنَّهُ لاَ يَدْخُلُ الْجَنَّةَ إِلاَّ مُؤْمِنٌ وَهِيَ أَيَّامُ أَكْلٍ وَشُرْبٍ ‏"‏ ‏.‏
Grade :  Sahih (Darussalam)
Reference : Sunan an-Nasa'i 4994
In-book reference : Book 47, Hadith 10
English translation : Vol. 6, Book 47, Hadith 4997