
If objective moral values exist (things that are truly right or wrong regardless of opinion), they require a foundation beyond human convention. Naturalism cannot ground objective morality, but theism can. God's nature serves as the standard of goodness, and His commands constitute our moral duties.
Objective moral values exist (e.g., torturing innocents is wrong)
Naturalism cannot ground objective morality
God's nature provides the moral foundation
Moral experience points to moral reality
C.S. Lewis, Mere Christianity