I am the Devil - I am a deceiver! I will lead you into Hell!
(Ralph Venning, "The Plague of Plagues!" 1669)
"No wonder, for even Satan disguises himself as an angel of light!" 2 Corinthians 11:14
The Devil disguises himself as an angel of light - that he may more effectually lead us into darkness. If he were to come like a devil, like an enemy - then everyone would run from him. But he comes masked and puts on the face of a friend - and so he tricks and cheats us. Indeed, he prevails more by his wily subtleties - than by his power.
If the Devil had come to Eve and spoken to her as follows: 'I was once a glorious angel and lived above in the Court of Heaven - but I have sinned and am now cast down to Hell. Eat the forbidden fruit - and you will be like me!' Would this have succeeded? Surely not!
Thus if he came and tempted men to sin, by telling them that sin is the sure way to Hell - would this prevail with them to sin? No! The Devil is a subtle old serpent - he cloaks and paints sin. He covers his hook with a bait - and draws men in before they are aware of it. He is a deceiver - and lest he should be known, he puts on a false garb and disguises himself as an angel of light.
He dare not say, "I am the Devil - I am a deceiver! I will lead you into Hell!" - for that would spoil his wily schemes.
"Watch out for false prophets. They come to you in sheep's clothing, but inwardly they are ferocious wolves" Matthew 7:15