I know of no true source that reveals "religion is meant to create love and unity"
From Genesis...
Religion originated in the garden of Eden, after Adam and Eve sinned, and it is a form of worship different to the worship of the creator.
Hence religion originated with the Devil, not God.
The Devil''s lies were further spread through many forms of worship, after God confused the languages at Babel, and men carried their religion far and wide, eventually developing into different forms.
Religion
Meaning - a form of worship.
Worship of the true God is not a form, but the only right and true way to worship God - acceptable to him.
This explains the reason why religion is divided, and never will unite.
Some will get along, since there are from the same source, but they will always be conflict between the true way, and the false - all the various forms of worship.
I think that the moral teachings of all religions tell us to treat others how we wish to be treated. We all want to be loved and accepted I believe.