It is normal for people to wonder; if the consequences of sin is hell, but the Christian will never go to hell, then what is preventing them from living a life of unbridled sin, seeing as there are no apparent consequences, and whatever they do they will be forgiven?
The first thing we need to acknowledge is the fundamental assumption behind this question. This is that the threat of hell forms one's motivation to be good. Based on that assumption, one would suppose that if they would just be good, constantly, they would escape an eternity in hell. But this isn't the case. Unless you are perfectly good you will go to hell; and not one person is perfectly good. Whatever chance you had at being perfectly good, you've already blown it. The threat of hell is not, in fact, motivation to be good. Rather, the threat of hell ought to motivate us to seek a saviour; the Saviour, Jesus Christ, because our situation is hopeless. We are not righteous enough to escape hell and get to heaven. The perfect righteousness of Christ is “counted as [our] righteousness” through faith in Christ...
And to the one who does not work but trusts him who justifies the ungodly, his faith is counted as righteousness (Romans 4:5)
So what stops a Christian from sinning? When I was a teenager, before I was a Christian, my parents who are both Christians said to me; “We have found that, as Christians, we don't actually want to sin.” At the time, I didn't fully understand what they were saying. They were speaking about their own personal experience, and I lacked that experience. I understood that one might choose to live a moral life, but I didn't understand what I do now, experientially. That is, there is a complete change that takes place in us when we are born again. We call this “regeneration”. The Bible calls it being “born again” because spiritually, it is literally being “recreated”...
Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come. (2 Corinthians 5:17)
You see, when God created mankind, they were without sin. But it wasn't long before man corrupted himself through sin. This separated man from God; it literally made them enemies. But God desired to restore His creation to its former glory. This is why, in Christ, we are a “new creation”.
One might say, “If you're a new creation, then wouldn't it follow that you should stop sinning altogether?” Well, when a person is saved they are given a “new heart”, but they are not given a new body. Our very bodies are corrupted by sin, and so there is still corruption in us. If God wanted to, He could immediately renew us entirely and bring us up to heaven with Him to be rid of this corrupt world and to be with Him. But God doesn't do that. Why? Because we must remain here for the sake of those who do not believe... to bear witness of Christ in the midst of this corrupt world.
So we continue to live in a corrupt body, and we are still influenced by our old nature which remains somewhat bound to us. And it is difficult, especially at first, to know any different than what we have been up until then. I heard a story of a certain Biker who came to faith in Christ. He used to hang around the bars and strip clubs. When he became a Christian, he wondered “What do I do now?” The advice he was given was “Just go on living; you'll know what to do.” So off he went, as usual, to the bar. But as he was sitting there, he just looked around him and thought, “What am I, a child of God, doing here!?” And so he left, forsaking that way of life. In my own experience, when I became a Christian, I began to recognise the things in my life that I ought not to be doing. Some things were immediately obvious, and I stopped doing them; even things I had already struggled to quit on my own. Other things took me a little longer before I even realised that they were sinful in God’s eyes, or affecting my relationship with God. But a true Christian hates sin and doesn’t desire to do it. John says:
No one who abides in him keeps on sinning; no one who keeps on sinning has either seen him or known him. (1 John 3:6) [See also 1 Corinthians 15:34]
Now we also see sin all around us, and it is a temptation to us. It's true that Christians do fall into sin from time to time. However, the desire to sin is powerfully opposed at all times by the desire to do right, and to be obedient to God. Sin is always followed by true repentance. What is happening is that while in this world, God is transforming us, or restoring us, to the way we are supposed to be; the way we were originally created. This is a process which theologians call “sanctification”. Christ Himself is the perfect image of God (Colossians 1:15). Being without sin, He is what we are supposed to be like. So the Bible speaks of our transformation into His image, or likeness (Colossians 3:9-10). It is a process. The Bible shows us what Christ is like, and so shows us what we ought to be like. James writes the following in relation to this:
For if anyone is a hearer of the word and not a doer, he is like a man who looks intently at his natural face in a mirror. For he looks at himself and goes away and at once forgets what he was like. (James 1:23-24)
When we read the Bible we see who we truly are. But if we then go away and behave contrary to the Bible, it is the same thing as behaving like someone we're not. This is what a Christian does when they sin. It is not who they are. Christians are not excused by God when they sin. While Christians do not go to hell, they do not escape entirely the consequences of their sins. When a Christian lies or steals, he suffers the same consequences in this life as anyone else; and God Himself will discipline them in order to bring them to repentance. But in every true Christian is the sincere desire to do what is right, and to imitate the righteousness of Christ. If a Christian thinks in terms of “I can do this sin and get away with it; God will forgive me”, this may be evidence that he's no true Christian at all for he lacks evidence of regeneration.
Until tomorrow, here are the characteristics of the corrupt “flesh”, and the “regenerated spirit”
Now the works of the flesh are evident: sexual immorality, impurity, sensuality, idolatry, sorcery, enmity, strife, jealousy, fits of anger, rivalries, dissensions, divisions, envy, drunkenness, orgies, and things like these. I warn you, as I warned you before, that those who do such things will not inherit the kingdom of God. But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, self-control; against such things there is no law [ie; no prohibitions]. And those who belong to Christ Jesus have crucified the flesh with its passions and desires. (Galatians 5:19-24)