ʿAbdullāh the son of Al-Imām Ahmad reports that his father, Al-Imām Ahmad, said, “The graves of Ahl Al-Sunnah who committed major sins are gardens (from Paradise) whilst the graves of the heretics (adherents of Bid’ah) who were ascetics are pits (from the Fire). The sinners from Ahl Al-Sunnah are the beloved (awliyā`) of Allāh, whereas the ascetics of Ahl Al-Bid’ah are the enemies of Allāh.”
Ibn Abī Ya’lā, Tabaqāt Al-Hanābilah Vol. 1 p182.