The English dictionary defines religion as:
The belief in and worship of a supernatural controlling power, especially a personal god or gods.
There has been much controversy on the issues of religion as different ethnic groups consider different forms of worship. History seem to have been the basic of people's belief, the christians believe in the history of the bible living a Christ-like life, the Muslim believe in the history of the holy Mohammed, the indians, Japans, and other part of the world have a history which form the root on what they believe and no one seem to be wrong as they carry out their religious rite.
Disciples of Jesus were called "Christians" in Antioch when some groups of fellows realized they were living a life similar to Christ. At that time it wasn't a religion, it was just a lifestyle of Jesus whom they have followed for a period of time, therefore, religion is not a worship, it's a lifestyle. Remember I said earlier that every religion was born from the history of someone who once lived a long time ago whose character was worthy of being emulated . People saw them as god and therefore chose to follow his path.
To me, religion is not the public display of going to church, singing, and praying aloud for people to approve of us being holy. Even Jesus condemned such acts during his ministry, he understood how people hide under the name "religion" to rob people. Therefore, true religion is to give to orphans and widows in their trouble and to see oneself unspotted before God. Religion is about doing good and staying righteous unspotted from the things that defile us as humans. Going to church is good but that doesn't define a true religion, the prayers and worship is good but that also isn't true religion, religion is seen in the life that we live. It was because the disciples had emulated the life of Christ that they were referred to as christians.
Paul during his time of ministry told the people their life is the epistle people read. Yes, we may go to church, sing songs, pray, worship, etc. But what people see is that which you do (the kind of life you're living). I believe when we do be judged, it would be by what we did while we were on Earth, whether we lived a life worthy of approval or not.