A paralyzed man with four good friends discovered that Jesus was the one who had authority to forgive sins. He'd been carried by his friends to Jesus because they believed Jesus could heal him. He might have been as surprised as everyone was that before healing him Jesus declared his sins forgiven. 

Some people who heard these words were offended. Only God can forgive sin, they correctly thought. But Jesus proved he could do better than just say the man's sins were forgiven, he could do what what was clearly harder to do, tell the paralyzed man to get up and walk. He did so, and the man got up and walked, proving Jesus can forgive sins. Yours and mine, too.