What if there was no such "person" as Satan? Or God?
Then we would have lost the meaning of Hope.
As we are born of flesh, which is weak and self-centered, we are inclined to wallow in laziness, apathy, greed, despair, rage, hatred, or whatever pleases our senses and dulls our fear.
The entirety of existence is polar; good or bad, hard or soft, light or dark, up or down, close or far to name just a few opposites. We would prefer to balance in the middle but we tend to slide down the slippery slope toward the dark side. Going toward goodness and light requires effort and sacrifice.
Without much thought, most people proclaim they want to be good, they want to be known as having all of those qualities on the positive side of the balance sheet but, again, most "goodness" requires effort and sacrifice.
No one can rise above their flesh to sustain effort and sacrifice without some help. And most of us cannot go beyond our own limitations to help someone else with their effort and sacrifice.
What it all boils down to is a need for un-natural, or super-natural, assistance to get motivated, to strive, to struggle and to sacrifice one's own desires toward the good/positive/light side of qualities and endeavors.
Thus the need for God - the Good; and a patsy for evil - Satan.
