Pick any sin/immorality... now...
It's wrong to ____. Says who? Society? Whose society? The government? Whose government? Culture? Whose culture? Conscience? Whose conscience?
Says GOD! The GOD! All other authorities change and degrade without GOD. GOD must be the authority.
We cannot hope to maintain good morals without GOD. Look at our own culture, society, government, and even our own consciences. The more we leave God out, the more our morality slips away.
It's wrong says who? Says GOD!