Our first parents fell into open disobedience because already they were secretly corrupted; for the evil act had never been done had not an evil will preceded it. And what is the origin of our evil will but pride? For “pride is the beginning of sin.” And what is pride but the craving for undue exaltation? And this is undue exaltation, when the soul abandons Him to whom it ought to cleave as its end, and becomes a kind of end to itself. This happens when it becomes its own satisfaction….The devil, then, would not have ensnared man in the open and manifest sin of doing what God had forbidden, had man not already begun to live for himself….By craving to be more, man became less; and by aspiring to be self-sufficing, he fell away from him who truly suffices him.
–Augustine, The City of God 14.13
It is precisely for this reason – that the potential for sin existed in us before the act – that there is no reason to posit a separate Satan. He is in us, and has been from the outset; this is the price of freedom of the will. If we lacked the power to do what was wrong, we would never do it, so the power had to preexist. The notion that there is a separate being called Satan is a redundancy, a scapegoating to avoid facing what we all know and have known, that the desire to do what is wrong is great because what is wrong is where the greatest flavor is on the roast. Sin may be a bad habit, but it is a richly rewarding indulgence. Temptation is the test God has created so that our free will can be real. Larry