Many scriptures speak of the authority of Jesus. Today's first reading points out that God the Father subjected all things under Jesus. It's a quote from the responsorial Psalm. And the Gospel story shows us that Christ's authority is so powerful that the demon had to depart from the man whether it wanted to or not.
Do you suppose that the reason why evil remains in this world -- and in your life -- is because God doesn't have enough authority on earth to get rid of it all? Maybe Satan is in charge of this world and God only has total authority in heaven? In our daily troubles, as the hardships continue unrelentingly despite our pleas for divine help, it seems like God's will is being overpowered by the devil or by the free will of the people who are causing the hardships.
But Christ's authority is superior to all! It is the ultimate authority and the final authority. As he told Pilate, no one has any authority except what is allowed by God. The worst enemy that our world has gets his authority from God. Granted, it's misused, but God has the power to withhold the breath of life from him at any moment and thus put an end to it. He could have struck Pilate dead with a lightning bolt -- wouldn't that have knocked the socks off all those who were yelling "Crucify him!" And a hidden, greater plan would have been side-tracked.
Christ's authority is not dependent upon anyone's conversion. Notice that the people in this Gospel story asked, "What does this mean?" -- a sure sign that they did not yet believe he was the Messiah. And the demon certainly did not convert into a good angel; yet he obeyed.
There are many examples of Jesus' authority today. We see it when a baby is baptized: Unable to know God personally, the infant is nonetheless impacted by divine authority as Jesus cleanses the child from Original Sin and the Father adopts the child and the Holy Spirit fills this tiny person with divine gifts.
Every request for divine help is acted upon by God -- every request! -- with that same strength of power and authority. Yet when we pray, we assume that we have to beg Jesus to respond. We get mad at the people who stand in the way of the answers to our prayers. We worry that the Lord won't overcome the evil that's harassing us. What a wimpy, faithless way to pray!
Instead of telling Jesus what kind of help we need, we accomplish much more if we pray IN his authority. That means we let him decide how and when and through whom our prayers should be answered.
Prayer doesn't change God (thank God for that or we'd surely worsen our messes!). True prayer changes us so that our will becomes aligned with his will and we begin to cooperate with his hidden, much better plan.