The devil is an unclean spirit, because he has lost all the purity of his nature, because he acts in direct opposition to the Holy Spirit of God, and by his suggestions defiles the spirits of men. There are many in our assemblies who quietly attend under merely formal teachers; but if the Lord come with faithful ministers and holy doctrine, and by his convincing Spirit, they are ready to say, like this man, What have we to do with thee, Jesus of Nazareth! No disorder could enable a man to know Jesus to be the Holy One of God. He desires to have nothing to do with Jesus, for he despairs of being saved by him, and dreads being destroyed by him. See whose language those speak, that say to the Almighty, Depart from us. This unclean spirit hated and dreaded Christ, because he knew him to be a Holy One; for the carnal mind is enmity against God, especially against his holiness. When Christ by his grace delivers souls out of the hands of Satan, it is not without tumult in the soul; for that spiteful enemy will disquiet those whom he cannot destroy. This put all who saw it upon considering, What is this new doctrine? A work as great often is wrought now, yet men treat it with contempt and neglect. If this were not so, the conversion of a notorious wicked man to a sober, righteous, and godly life, by the preaching of a crucified Saviour, would cause many to ask, What doctrine is this?