If God were not my friend, Satan would not be so much my enemy.
Satan can never undo a man without himself; but a man may easily undo himself without Satan.
He who sups with the devil had better have a long spoon. The devilry of modernity has its own magic: The [believer] who sups with it will find his spoon getting shorter and shorter-until that last supper in which he is left alone at the table, with no spoon at all and with an empty plate. The devil, one may guess, will by then have gone away to more interesting company (Peter Berger).
[Knowing the character of ] Satan, we may easily judge who his children are. They are those who love to tell a lie, who slander and speak evil of their neighbor, and whose hearts are full of pride, deception, hatred, envy, revenge, and cruelty. Surely they have Satan for their father: for they know Satan’s character and they do the works of Satan. But if they could either see themselves, or Satan as he really is, they would be terrified at their resemblance to him, and totally hate themselves with a deep remorse.