Grant puts it like this:
Unless you have a proper understanding of sin -- especially the sin in your own life -- you don’t really understand why Jesus came into this world, why He said the things He said, why He did the things He did, and why He died and was raised to life again. The first act of Jesus’ public ministry was His baptism by John. As Jesus came to the Jordan River, John declared (John 1:29), “Behold, the Lamb of God, who takes away the sin of the world!”
Since the first humans decided that they wanted to “be like God,” the world has been plagued -- literally cursed -- by sin. In the healing of the paralyzed man at Capernaum (recorded in Matthew, Mark, and Luke), Jesus reveals the “sickness” from which human beings are in most need of a cure. After his friends went through the difficult work of getting their paralyzed friend to the roof of a crowded house where Jesus was teaching, and after they labored to lower their friend into the room so that he could get closer to Jesus, what were the first words out of Jesus’ mouth? As the Book of Mark records, Jesus, seeing the faith of the paralyzed man and his friends, immediately declared to the man, “Son, your sins are forgiven.”If we fully understand our own sin, we will see that the things that supposedly "happen" to us are the result of our own sin, and that of others. We can only thank God that he does not execute upon us the just temporal and eternal punishment we deserve. For the true Christian, every moment of every day is an act of contrition and repentance. But then we remember the story of the Prodigal Son (Luke 15: 11-32). There is great rejoicing in Heaven when one returns.