What is difference between religion and moral belief system?

Answer

People can hold religious beliefs and moral beliefs, in fact many do. But it is also possible to follow a religion without holding any strong moral principles, or to hold to a moral belief system without having any religious beliefs.

Some ancient religions were little concerned with moral principles, as long as the gods were worshipped properly. Even today, some Christians believe that moral failings or sins will be forgiven as long as they believe, arguably making moral principles optional.

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Here is a useful way to think of the difference. Religion is a set of practices, and it can be reasonably independent of belief system or faith. For example, religion involves the manner in which you worship, if you choose to worship. Do you attend a church or other house of worship regularly? Are you a member of the fellowship that you attend? What are the rituals used? What is the order of worship? (The things that go on during a service including use of music, various kinds of postures or gestures while worshiping, teaching and/or preaching based on a set of special texts, etc. Some people have engaged in religious worship for years without giving much thought to faith, or to the beliefs that support a fellowship's religion.

A moral belief system can be based on faith or related to religious practice, but it can also be independent of religion and faith. It has to do with what a society considers to be acceptable behavior and acceptable positions to hold regarding most aspects of life, inter-action and relationships.