Sufyaan ath-Thawri said,
“Innovations are more beloved to shaytaan than sin, since a sin may be repented from but an innovation is not repented from.” [Sharh Usool I’tiqaad of al-Laalikaaee (d. 414h) no.238, the great 4th century Imaam who wrote on the belief of Ahl usSunnah.]
This is because the innovator believes he is doing something good and therefore sees no need to repent. He also said, “…so cling to the original state of affairs,” [al-Hilya 6/376] meaning the way of the Prophet sallallaahu alayhi wa sallam and his companions.
AbdurRahman.Org 