A famous Bible passage says “For all have sinned and fallen short of the glory of God.” I’ve always known myself to be a sinner. I watch myself. I know things that I should do that I flatly and knowingly refuse to do. Sometimes, I do what I should, but with a lot of grumbling. Sometimes I pretend that I don’t know the right thing or make lots of excuses. I just want to do what I want when I want. I don’t want to be forced to live differently from how I wish, even when God is the one giving the orders.
That’s sin: refusing to submit to God. Some people think that sin is stealing, or lying or murder. Those are sins, but they are sins because they all share that one thing – a refusal to submit to a law, to be made to act differently than we want to. That’s also how one can be a sinner without having ever committed a sin. It is not lying or stealing that makes us sinners. We are sinners because we refuse to submit to God and we sin because we are sinners. As children we want what we want. We have to be taught to share and to obey instructions. We have to be made to obey rules because we would not do the right thing on our own. That is why no one can claim to be righteous.
All through human history, we have developed methods of working around this problem: indoctrination, punishment, rewards, deterrents, encouragements. None of those are perfect and none of them solve the problem of human nature. But Christianity claims to. It claims that God has come up with an ingenious way to create new beings out of us, to take out that sinful nature from us and give us natures that will love and submit to him. So that instead of taking the consequences of our acts, we can enjoy eternity with him.
Therefore, there is now no condemnation for those who are in Christ Jesus,because through Christ Jesus the law of the Spirit who gives life has set you free from the law of sin and death. For what the law was powerless to do because it was weakened by the flesh, God did by sending his own Son in the likeness of sinful flesh to be a sin offering. And so he condemned sin in the flesh, in order that the righteous requirement of the law might be fully met in us, who do not live according to the flesh but according to the Spirit. – Romans 8: 1 – 4