Raised to Walk in the Newness of Life

One of the biggest misunderstands I had of first coming to Christ is thinking it was a self-improvement program. We're looking at it from a human perspective, not a Godly perspective. But it's not about self-improvement. It's about Jesus Christ - dying in Christ and being raised with him to walk in and through his power. We need to remember who we are in Jesus Christ. What do you say to the statement, "If you don't behave God will harden your heart"?What about those who die apart from Christ? What happens to them at their death?Please clarify Hebrews 10:28,29 "Anyone who has set aside the law of Moses dies without mercy on the evidence of two or three witnesses. How much worse punishment, do you think, will be deserved by the one who has trampled underfoot the Son of God, and has profaned the blood of the covenant by which he was sanctified, and has outraged the Spirit of grace?"What can we say about believers who are caught in drug addiction?