What does Mark 5:7 mean?

The Bible does not give the reason that Jesus wanted to cross the Sea of Galilee other than to escape the crowds on the western shore. The legion of demons (Mark 5:9) assume Jesus is there for them. "Adjure" is from the Greek root word harkizo which means to implore or beg. Although demons had revealed Jesus' identity before (Mark 1:24), by using Jesus' name and the phrase "by God," the demons here are attempting much more than just asking a favor. There is a pagan belief that if you know someone's name you can control them. The demons aren't just requesting Jesus leave them alone; they are trying to magically force Him to make an oath in God's name.

Of course, as God, Jesus is not bound by any demonic attempts, despite the fact He does not torture the demons. The Greek root word from which "torment" is derived is basanizo and means to determine something's purity or to use torture to get information. God is omniscient; He has no need of information from demons and He's well aware of their unrighteous state. In all Jesus' encounters with demons, He never tormented them. He just told them to leave.

Interestingly, this statement may give us insight into the question of why Satan thought he could defeat God (Isaiah 14:12–15) and why one-third of the angels in heaven followed him (Revelation 12:3-4). If these demons thought they could control Jesus, or influence His actions in any way, they don't fully understand the power of God. We make the same mistake when we try to manipulate God to do what we want, rather than relying on His will.