God is the moral standard everything which he orders then becomes morally right. How can we determine what is right or wrong with God? And if right or wrong is only determined by harm is incest ok if no children come of it.
If you have to be afraid of the sky papa to be good to other people you are not good, you are just afraid of being punished.
Morality is a socio-cultural idea, there's no such thing as natural morality, we consider things right and wrong based on interactions of the culture we are in with some psycological drives common to primates like empaty and group well being.
This idea that moral is some kind of religious thing is just another way of ultra-religous people trying to force their religious rules in another people life because they fell bad that another people can enjoy pleasures of life that by some religious "rules" they can't, and still have a happy life.
Even the Pope had already said that is better to be an atheist who respect and do good for other people than a religious who do bad and try to force his way on people.