Jesus said to the Pharisees, "For Which is easier, to say, 'Your sins are forgiven', or to say, 'Rise and walk'? But that you may know that the Son of Man has authority on earth to forgive sins" (ESV).
Jesus is saying, "I do not only have power over nature; I have power over sin. I am not only Creator, I am also Redeemer."
Sin threatened to limit God's power in the universe, but by His death and resurrection, Jesus has extended the power of God to include authority over sin (Matthew 28:18).
Therefore, the same power that brought this world into existence and sustains it, is available to cleanse and to heal the soul from sin (Colossians 1:16, 17).
Now, God doesn't only create the sea, land, sky and their inhabitants, He is able to make a drunkard sober. He is able to make the promiscuous pure; He is able to cleanse the heart of adultery, murder and covetousness.
And just as how God created this world out of nothing; He can make something out of my nothingness.
Whatever condition my soul is in, by the word of God, He can fix it.
I thank God, that the Son of Man has power, not only to heal the body; He can heal the soul.