As a kid growing up, and admittedly even as an adult, I always thought/assumed that evil first entered the world when Adam and Eve disobeyed God's commands when they ate the fruit from the tree in the middle of the garden. However, we see pretty obviously in Genesis 3 that evil was already in the world (crafty serpent) prior to this event. We learn that the crafty serpent (the Devil) had fallen from Heaven and is now tempting Eve. What caused the Devil to fall from Heaven? Was he called "Devil" when he was still in Heaven amongst angels such as Michael and Gabriel? We'll find out someday.
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