Sunan an-Nasa'i, Hadith 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 " .
also referenced under: Book 47, Hadith 10 (In-Book) & Volume 6, Book 47, Hadith 4997 (DarusSalam)