Mark 5:16-20

Mark 5:16 (KJB)
And they that saw it told them how it befell to him that was possessed with the devil, and also concerning the swine.

Now once again the herdsmen had told the people about all the events which took place. They had told the people that the man who was possessed with the devils had now been delivered and was in his right mind. No longer would he be a physical threat to anyone. Now they had included the situation with the dead pigs. There must have been great consternation concerning the killing of these 2,000 pigs because now they had 2,000 pig carcasses all over the shore of the Sea of Galilee. Someone was going to have to clean them up and transport the bodies someplace else or the sea would become contaminated and maybe kill a large portion of fish. It would also be a source for disease, especially plague if the bodies start decaying and they become filled with insects which would fly away and carry disease to the people.

Mark 5:17 (KJB)
And they began to pray him to depart out of their coasts.

Once word had spread concerning the events which took place, the entire town had come out to see Jesus. No longer was the focus on the devil possessed man and his deliverance, they now focused strictly on Jesus. They saw the delivered man sitting clothed and in his right mind. They were all still probably frightened of him knowing his history but now they are seeing him in a different light. However, the people were obviously frightened of Jesus and asked Him to leave the area because they had just lost a huge herd of swine which would have been worth much money. They had desired the pigs over Jesus, nevertheless, the two men whom Jesus delivered from the demonic possession had stayed behind and now there were two witnesses to the power of Jesus who had shown ultimate power over the kingdom of Satan.

Mark 5:18 (KJB)
And when he was come into the ship, he that had been possessed with the devil prayed him that he might be with him.

What a difference in attitude between the people of the town and the man who was delivered of the devils by Jesus. The people of the town were more concerned with the pigs and wanted Jesus to leave. The man who was delivered of the devils was so thankful, he wanted to follow Jesus as a disciple of His. You would think the townspeople would have welcomed Jesus because not everyone in the town owned the pigs so not everyone lost money.

Mark 5:19 (KJB)
Howbeit Jesus suffered him not, but saith unto him, Go home to thy friends, and tell them how great things the Lord hath done for thee, and hath had compassion on thee.

Although Jesus knew how thankful this man was, yet He did not allow him to become a disciple of His, that is, one of the traveling disciples. However, Jesus commanded him to go home to his friends and family and testify to the fact of how Jesus had delivered him from the devils. In this manner, he became a disciple because he testified to all the things the Lord had done. Place yourself back in that village where his friends lived. Can you imagine what they thought when they saw him coming into town? They probably grabbed all the children and brought them inside and then hunkered down expecting a demonic tirade. His basic testimony was that he was delivered from the devils and now in his right mind. He can now testify to the compassion the Lord had on him in contrast to the scorn all the people had toward him when he was possessed. This is the normal routine for the majority of those who become saved. Not everyone will be sent to some foreign land as a missionary but will be a testimony right at home.

Mark 5:20 (KJB)
And he departed, and began to publish in Decapolis how great things Jesus had done for him: and all men did marvel.

So the man did as Jesus commanded him and that was to return to his home. I would not doubt for a minute that his reputation proceeded him being possessed with the devils in such a visual manner. So his ministry was to Decapolis where he had began to publish or proclaim what the Lord Jesus did for him in delivering him from being possessed by devils and freeing him. His testimony was also telling the people what a tremendous authority Jesus has over the kingdom of Satan. Decapolis was a group of ten cities on the eastern side of the Sea of Galilee, so his area of ministry was very large. These smaller ministries had laid the groundwork for the ministry of the Apostles after the Holy Spirit would be given to them on Pentecost. It prepared the Gentiles to hear the Gospel in its fullness when time was right.