There is a big difference between being a Christian and being religious, although it is not uncommon for the two to be used interchangeably. Some may assume if they follow the rules and regulations of a specific church or religion, they are Christians. However, the only true way to be a Christian is to have a personal relationship with Christ himself.
Works versus grace
Religion focuses on the work or rituals a person must do to earn eternal life. For instance, if you do enough good work you will get to heaven. Christianity is based on grace and Christ dying to give believers eternal life.
Relationship versus no relationship
Christianity is a personal relationship with Christ who loves all and extends His grace to all people who seek him. Some may have difficulty understanding how humans can have a relationship with Christ himself. It is helpful to view it in a similar way as you would a parent and child relationship, as parents love their kids deeply and are willing to make sacrifices for their children, just as Christ's love is deep and sacrificial.
You cannot have a relationship with religion because it is not about a person. Religion is focused on striving to do everything right in order to please whatever entity a specific religion believes in. Religious regulations are impossible to live up to because humans are not perfect and keeping a specific set of rules and law is burdensome.
One way versus many ways
Religion is broad and can encompass believing in a variety of things whereas Christianity is only centered on a belief in Christ. Religion is focused on the works of man. Those who consider themselves religious may find themselves always seeking a new way to find happiness.
Christians are focused on their relationship with Christ and feel grateful for the ultimate sacrifice he made for their sin to be forgiven by His grace. This allows Christians to rest in the peace Christ gives them because there is nothing they must do to earn His favor, as He already made the sacrifice for them.
Being religious can mean many different things for people but it is important to know it is not the same as being a Christian. The mark of a true Christian is having a personal relationship with Christ. Belonging to a certain religion may make you appear religious where regular communion and fellowship with Christ on a personal level is the mark of true Christianity.
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