Christians often argue that atheists can't possibly have morals.
This tells us something very important about Christians. It tells us that whatever it is that makes Christians morals is something that atheists can't possibly have. It also tells us that the things that make atheists moral are not anything that inspires morality in Christians. After all, if it were, then they would not argue that morality is impossible for atheists.
Thus we know that the screams and cries of their victims would not be sufficient to stop a Christian from doing unspeakable things to random strangers, and why they cannot understand that most atheists find this a valid reason to not do horrible things to anyone, much less strangers.
We know that the well-being of others cannot possibly motivate Christians to do moral things, and why they cannot understand that most atheists find this a valid reason to be moral.
Whatever it is, it must be something that only people who believe in deities have.
This brings us to the
Euthyphro dilemma, first proposed thousands of years ago. While the argument was originally made about getting morality from gods, the same argument can be applied to
any authority. An authority can only demand your obedience, not make you more moral. Authority-based moral systems result in the
most extreme and incoherent form of moral relativism imaginable. Under authority-based moral systems, morality is completely arbitrary based on the whims of the "gods" (or to be more precise, the whims of the humans who write the holy books and the humans who stand in the pulpits).
So you must kill people who eat shellfish.
You must kill people who pick up sticks on the wrong day.
You must kill women who are not virgins on their wedding night.
You must kill disobedient children.
You must not eat pork.
You must not eat beef.
You must not eat meat.
You must pray five times per day.
You must have extra funerals on the 1st, 5th, and 10th anniversary of a loved one's death.
You must wash your hands a particular way before you pray.
You must die in battle in a particular way.
You must kill people who leave your religion.
You must disown family members who leave your religion.
You must pray before meals.
You must not eat meat and cheese together.
You must splash water on a baby's head in a very specific way in a very specific ritual.
You must not shave.
You must wear a silly hat with a dagger in it.
You must not eat meat unless the animal has been killed in a particular way.
If you are a woman, you must cover your hair when in public.
If you are a woman, you must cover your hair with a wig when in public.
If you are a woman, you must cover your hair when in church.
You must not eat meat on Fridays, but you can eat fish on Fridays.
You must not sit next to a member of the opposite sex when in public, even if it means delaying a flight for hundreds of people.
Arbitrary. All of it completely fucking arbitrary. That's what happens when you define morality by obedience instead of by the consequences of your decisions.
