Sayyiduna Bishr bin Suhaym (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) addressed us during the days of Tashriq and said: "None will enter Paradise except a believer, and these days are days of eating and drinking."
Hadith Referenceالمعجم الكبير للطبراني / باب الباء / 1198