How do you define religion?

My teacher for Philosphy and ethics recently asked me to do some extra essays and background reading after i didn’t quite get the grade i was expecting from a recent exam. I thought I might share a very short essay i have just done, as its quite an interesting topic. Before you carry on, this is my opinion on the matter and is open to dispute.
How do you define religion?
It is certainly difficult to explain what exactly the definition of religion is. If one attempts to describe it in terms of belief in God, Buddhism wouldn’t be considered a religion and comparatively, Any organisation or collective group would be labelled a religion if the definition of “a group in which all members have similar moral beliefs and goals” were used. A more accurate definition would perhaps be found by comparing the world religions and by discussing what common concepts they share.
Firstly, take for example the Abrahamic religions-Judiasm, Christianity and Islam. The important characteristics of these faiths are the worship of on ‘true’ God and sticking to a moral code written in their respective holy scriptures. Their ultimate goals are to serve God as well as they can in the way the Bible, Torah or Q’ uran has told them.
This differs dramatically from Buddhism, where no God is present in the faith. Instead, Buddhists follow the example of the Buddha to find enlightenment and escape the neverending cycle of reincarnation, which is often considered to be a state suffering in the faith. Yet there is an obvious similarity between the Abrahamic religions and Buddhism; the concept of reaching a spiritual goal.
Does this link remain there with Hinduism? It is a little harder to say in comparison to other faiths, due to the complexity and variation of Hindu worship. If we use one common idea-that all hindu Gods are in fact aspects of Vishnu and is part of everything in existence, we see the link again. If Vishnu is part of everything in existence, then there is a spiritual link between everything.
Conclusively, we can see that what most religions have in common is spiritual awareness and goals, be there a God or not. Abrahamic fiaths have spiritual goals to become closer with God, Buddhism focusses on the journey to spiritual enlightenment and Hinduism acknowledges a spiritual link and awareness between all things in existence. It is therefore not belief in God that separates moral organisations from religions, but spirituality is what makes an organisation a religion.