On the day of Khaybar the Prophet (peace and blessings be upon him) declared certain things unlawful, among them the domestic donkey and other things. He (peace and blessings be upon him) said: "Soon a man will sit on his couch, while my hadith is narrated, and he will say: Between me and you is the Book of Allah (and it is sufficient); whatever we find in the Book of Allah, what it makes lawful we will regard as lawful, and what it calls unlawful we will regard as unlawful. And the Prophet (peace and blessings be upon him) too has made things unlawful just as Allah Most Pure has made them unlawful."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 13442