AuthorityMark notes that Jesus was teaching in Capernaum, his base of operations in his earthly ministry. Capernaum was a fishing town on the northern shore of the Sea of Galilee. It was also probably Peter's home town. Luke says it was also the home of Andrew (Simon Peter's brother), James and John and Matthew. In Jesus' day, it had a population of about 1,500. Many years ago, I was able to sit in the excavated remains of the ancient synagogue there and look out over the waters of the Sea of Galilee.
In that same synagogue nearly two millenia earlier, Jesus was teaching as one having authority, and then just to prove his authority, he casts out an unclean spirit from a man. This passage is meant to get us thinking about Jesus' authority.
Exousia is the Greek word for authority. It means having the power of choice, the freedom to do what you please, the power to issue commands that must be obeyed. Stephen Hultgren of Fordham University calls it a sovereign freedom.
All the people at the synagogue note that Jesus is not like the other teachers. His authority to teach is backed up by the powerful exorcism he performs. Over the course of Mark, not only will spirits (sickness and disease) obey Jesus, but even the wind and sea (natural elements) obey him when he calms the storm. Hultgren says that the difference between Jesus teaching and the teaching of the other scribes in the synagogue is that they depend on the authority of the scriptures (Torah) and tradition. Compare that to Jesus' authority which is proved by his words and deeds (casting out spirits, healing, commanding forces of nature).
In other words, Jesus broke the mold, and instead of relying on the authority of scripture, goes directly to the very authority of God. And all of this consideration of Jesus and his authority, culminates in the idea that Jesus has the authority to forgive sins. (Mark 2:10).
Exousia also means arising out of the essence of something and arising out of a person's very nature, a function of their substance, in fact the homo-ousia clause of the Nicene Creed says that Jesus and the Father are made out of the same substance (or stuff).
So, Jesus' authority is a natural outgrowth of who he is, made out of the same stuff as God. Compare this to the authority of Presidents, Governors, Congressmen or judges. Their authority does not come from their own substance, but rather from the office entrusted to their care by our government. The authority is invested in them, not a matter of who they are, but rather what office they hold.
So, the next time you think about an authority (judge, professor, physician, pastor) think about how all of our authority is completely different from, and inferior to, Jesus' authority.