Original Sin

Thoughts of God's love for you will make for a contented life, focus on the gift of life alone not on your purpose, because the meaning of life is outside of your understanding. Replace all thoughts of carnal pleasure because when a person focuses on what is outside of their control: anxieties ensue, and your anxious thoughts will destroy your happiness and limit your free will.
Never, never believe that you are alone, that you can do whatever pleases you; it is easy for a person to conduct themselves with all their passions, but there are divine consequences for those unsanctioned pleasures.
The characters in this story said yes to their desires, leaving them no longer in control of their own actions: losing their soul.