- If God does not exist, objective moral values & duties do not exist.
- Objective moral values & duties do exist.
- Therefore, God exists.
Now this is a good argument because 3 follows necessarily if premises 1 & 2 are true; thus producing a sound argument.
Premise 2 seems intuitively obvious to most people. Hitler was objectively wrong. Torturing babies for fun is objectively wrong. Human trafficking is objectively wrong. 'Objective' simply means that it is true regardless of whether anyone else thinks so or agrees etc. It is a fact of our world. Honestly if someone denies premise 2, they don't need an argument, they need to get help.
It seems to me the issue is premise 1. Is God necessary to objectively ground morality? We will explore that in another post.
Until then, listen to a debate on this issue - Is God Necessary for Morality?
To see the argument in book form, check out Reasonable Faith by William Lane Craig.