The devil is a constant enemy to the Christian’s soul. That great, sleepless, and unwearied foe is always laboring to do us harm. It is his constant object to wound, hurt, vex, injure, or weaken–if he cannot kill and destroy. He is an unseen enemy who is always near us, “about our path, and about our bed,” and spying out all our ways, prepared to suit his temptations to the special weak points of every man. He knows us far better than we know ourselves. He has been studying one book for 6000 years– the book of fallen human nature, and he is a spirit of almost boundless subtlety and cunning, and of boundless malice. The best of saints has little idea how many vile suggestions in their heart come from the devil, and what a restless adversary stands at their right hand.
~ J.C. Ryle
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