It is narrated from Sayyidah Aishah (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) said: "There are six whom I have cursed, and the supplication of every prophet is answered: the one who adds to the Book of Allah, the Mighty and Majestic; the one who denies the decree of Allah; the one who regards as lawful what Allah has made sacred; the one who regards as lawful, regarding my family, what Allah has forbidden; and the one who abandons the Sunnah."
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2870