One of the most helpful ways of distinguishing between religion and the gospel is through this series of statements by Tim Keller. You can find these words in his message “On Being the Church in the Culture” from the 2006 Reform & Resurgence Conference.
Religion (salvation by works) v. Gospel (salvation by grace)
“I obey-therefore I’m accepted”
“I’m accepted–therefore I obey”
Motivation is based on fear and insecurity.
Motivation based on grateful joy.
I obey God in order to get things from God.
I obey God to get God–to delight and resemble him.
When circumstances in my life go wrong, I am angry at God or myself, since I believe, like Job’s friends, that anyone who is good deserves a comfortable life.
When circumstances in my life go wrong I struggle, but I know all my punishment fell on Jesus and that while he may allow this for my training, he will exercise his Fatherly love within my trial.
When I am criticized I am furious or devastated because it is critical that I think of myself as a ‘good person.’ Threats to my self-image must be destroyed at all costs.
When I am criticized I struggle, but it is not critical for me to because it is critical that I think of myself as a think of myself as a ‘good person.’ My identity is not built on my record or my performance but on God’s love for me in Christ. I can take criticism. That’s how I became a Christian.
My prayer consists largely of petition and it only heats up when I am in a time of need. My main purpose in prayer is control of environment.
My prayer life consists of generous stretches of praise and adoration. My main purpose is fellowship with him.
My self-view swings between two poles. If and when I am living up to my standards, I feel confident, but then I am prone to be proud and unsympathetic to failing people. If and when I am not living up to standards, I feel humble but not confident—I feel like a failure.
My self-view is not based on an view of my self as a moral achiever. In Christ I am simul iustus et peccator–simultaneously sinful and lost yet accepted in Christ. I am so bad he had to die for me and I am so loved he was glad to die for me. This leads me to deeper and deeper humility and confidence at the same time. Neither swaggering nor sniveling.
My identity and self-worth are based mainly on how hard I work, or how moral I am—and so I must look down on those I perceive as lazy or immoral. I disdain and feel superior to ‘the Other.’
My identity and self-worth is centered on the one who died for his enemies, who was excluded from the city for me. I am saved by sheer grace. So I can’t look down on those who believe or practice something different from me. Only by grace I am what I am. I’ve no inner need to win arguments.
Since I look to my own pedigree or performance for my spiritual acceptability, my heart manufactures idols. It may be my talents, my moral record, my personal discipline, my social status, etc. I absolutely have to have them so they serve as my main hope, meaning, happiness, security, and significance, whatever I may say I believe about God.
I have many good things in my life–family, work, spiritual disciplines, etc. But none of these good things are ultimate things to me. None of them are things I absolutely have to have them, so there is a limit to how much anxiety, bitterness and despondency they can inflict on me when they are threatened and lost.