Exorcisms are the only places in the Bible in which we get a glimpse into the character of demons. But more importantly, the exorcisms demonstrate God’s mercy toward those who were under demonic possession.
The gospels record Jesus having performed a number of exorcisms; many briefly noted and lumped with other miracles. Only five are told in greater detail. Like his parables, it is unknown whether the five were all of the exorcisms Jesus performed. The gospel writers could have told only the ones they each wanted to tell or wrote according to the sources available to them.
By performing exorcisms, Jesus extended his grace to a number of people—both male and female and of all ages. Jesus was apparently not concerned, as we might be, to ask what led these people to become demon-possessed. As with the woman caught in adultery, the thief on the cross and others, Jesus looked past their lifestyle and extended his grace on them because of his compassion. For one man to come across so many demon-possessed people within in three years seems astounding considering few people ever encounter a demon-possessed person in their entire lifetime. However, a wide array of cults—even mystery religions—was present in the region at that time, which could explain so many encounters. However, we cannot discount the leading of The Holy Spirit in Jesus’ ministry. The Holy Spirit led Jesus to the demon-possessed for the express purposes of revealing the Spirit’s power and the Father’s love.
An interesting case to study is whether Jesus actually extended his mercy to the demons as well. The synoptic gospels record a demon-possessed man in either Gerasenes or Gadarenes east of Galilee (Matthew records two men. It is possible there were two, but one was a spokesman) who was so tortured by numerous spirits that he/they could no longer be bound by irons and chains. Matthew records that the men were so violent, no one could pass their way. He routinely cut himself and howled, was naked and lived in the tombs. The spirits instantly recognized Jesus and begged him not to torture them or send them into the Abyss before the appointed time.
“A large herd of pigs was feeding on the nearby hillside. The demons begged Jesus, ‘Send us among the pigs; allow us to go into them.’ He gave them permission, and the impure spirits came out and went into the pigs. The herd, about two thousand in number, rushed down the steep bank into the lake and were drowned (Mark 5:11-13).”
Considering the torment they put this man (or men) through, Jesus had every right to cast the demons into the Abyss; but instead, Jesus granted the request of demons, setting them free. Was this because it was not the appointed time or was it out of mercy? The question can be debated, but if it is the latter, then just think how much more he will grant the request of his children. This is an amazing thought.
 House, Wayne H., Chronological and Background Charts of the New Testament (Grand Rapids, MI: Zondervan), 113-115
 Ibid. 88-89.
 Ibid. 193-194.