Satan

"The business of this false spirit is to deny the things that Christ has spoken which are written in the Word and, instead, to claim new revelations of his own, to lead men from the written Word in which the whole work of God and all the promises of Christ are recorded. Such was the spirit of the Montanists and that of Mohammed and of all who claim new revelations today."

-John Owen, Communion With God, Pg. 195