"And whoever does not take his cross and follow me is not worthy of me. Whoever finds his life will lose it, and whoever loses his life for my sake will find it."
Becoming a follower of Jesus brings us to one of the greatest paradoxes that the world will ever know - the gospel is free and Jesus paid the ultimate price for all our sins with no catch, but to follow Jesus will cost you everything. How does that work? The common Bible skeptic will look at that and find it makes no sense, but a careful study will show that nothing could make more sense than that.
I have a friend who is fond of adopting stray dogs and taking them in as her own. She considers it a small social responsibility project of hers to rescue dogs from the street and domesticate them. Many of these dogs were in terrible condition prior to being rescued but are now in great shape.
In some way or another, Jesus is very much like that friend of mine. Through His goodness and mercy, we have been adopted into the family of Christ and we are now sons and daughters of God, but the moment we are added into the family of God, we are also adopted into the culture and identity of His kingdom. We cannot keep acting like "stray Christians" when we are now part of the family.
What that means is that the moment we are born into God's kingdom, we are now no longer our old, sinful and selfish selves. 2 Corinthians 5:17 says it best: "Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come." Now that we are God's we have to die to our old self.
That's what Jesus talks about when He calls us to lose our life. No, God's not asking you to literally end your life then and there. The call to die to ourselves is the call to spiritually die to the old sinful nature and to be resurrected into new life with Him. In the Spirit, we are brand new - now in great shape and rescued, but also dead to our stray conditions.
Before the new and renewed can rise, the old must die so that the new can take it's place. The moment you give your life to Christ, God no longer sees the old you when He looks at you but now a new you established in the work and identity of Christ. As that happens, we progressively also die to our old habits that did not honour God. The Bible never promises instant change of behaviour, but it does point to a transformation of heart and as that happens, we gradually die to our old self losing who we once were now being born into the newness of Christ.
All this comes for free and God never expects us to pay back the grace of saving us, but He does call us to lose our old ways and now embrace His kingdom, His culture, His life and His identity.