If there is no absolute morality, then are you suggesting that if you were sold as a sex-slave at the age of 7, that would have been be ok? In which case(s) would child-sex-slavery be acceptable, or beneficial to the child? Or does it harm the child in every single case?
I pick this example for effect, but unless you're mentally ill, then I'm sure you'll agree there's no case in which the above is acceptable or beneficial.
If not, then why?
Because of the harm done to something you don't own - it's tort law.

Morality is law that has existed since the beginning of the Universe. It's part of natural law, and part of logic.
Religions are not moral organisations, they use a sprinkling of morality to sweeten the lies they feed people.

I'm always saddened when I hear how the evil Christian church has turned good people against God. The church does not speak for God, it's a fraud. Please use your logic - which leads to God - faith is not required. Belief is a hindrance. God is real and he wants you to know everything, not believe in some crazy fairy tale. God gave people brains so they could think for themselves. :)

Sure, give up on the church, they're useless, but don't conflate church with God (however much they want you to). Church is to God as fish is to golf.