The story of the Demon Possessed Man happens after the desciples get out of the boat. The story links prophetically to Noah’s flood and a period in history when the same demon was cast out.
1And they reached the port on the other side of the sea in the country of the Gerasenes.
2And, as he went out of the boat, he was met by a man from the cemetery, who had an unclean spirit.
3He lived in the cemetery, and no man could bind him in chains,
4because whenever he was bound with shackles and chains, he broke the chains and cut the shackles, and no man could control him.
5And always, night and day, he was in the cemetery and in the mountains, crying aloud and cutting himself with stones.
6When he saw Joshua from far away, he ran and worshiped him,
7and he cried with a loud voice saying, What have we in common, Joshua, son of the most high god? I adjure you by god, not to torment me.
8For he said to him, Get out of the man, unclean spirit.
9And Joshua asked him, What is your name? And he said to him, Our name is Legion, because we are many.
10And he begged him eagerly that he would not send him out of the country.
11Now there was near the mountain a large herd of swine feeding.
12And the lunatics begged him saying, Send us to the swine, that we may attack them.
13And he permitted them. And the lunatics went out and attacked the swine; and the herd ran to the steep rocks, and fell into the sea; they were about 2,000, and they were drowned in the water.
14And those who fed them, fled, and told it in the city and also in the villages. So they went out to see what had happened.
15And they came to Joshua, and saw the lunatic, clothed and well behaved, and sitting down quietly, even the one who once had the legion inside him; and they were afraid.
16And those who saw it told them just what happened to the lunatic and also to the swine.
17So they began to urge him to leave their border.
18As he went up to the boat, the lunatic begged him to remain with him.
19And he would not permit him, but said to him, Go to your home, to your own people, and tell them what master has done for you, and that he has had mercy on you.
20And he went away, and began to preach in the 10 cities about what Joshua had done for him; and they were all astonished.
In this area Jesus and the disciples encounter a man possessed by a demon. The man sees Jesus from afar and runs to Jesus, begging with Jesus that he not torment the demon, which is what the demon has been doing to the man. In all cases of deliverance the words that a demon speaks are related to the sin that gives them power and their nature or character that drives how they attack their victims.
In this case the demon easily acknowledges that Jesus is the son of the Most High God, suggesting the man has problems in this area. The demon does not want to leave the country, suggesting a problem relative to geography.
Finally, Jesus demands the name of the demon and from that dialog the demon’s name is revealed: Legion.
Demons gain their right of entry into people based on the sins of the individual. Delivering someone of a demon involves a process of discovery where the enabling sins are discovered and repented of. The full process of delivering this man is likely not covered in detail by Mark because he is telling a parable about some event in world history. That event is dated by the number of pigs that head down the mountain: about 2000.
Jesus and his disciples crossed the sea by boat, prophetically matching Noah’s ark. Now, following the standard rules for parables and time, 2000 pigs rush into the sea and are drowned. Those 2000 pigs represent 2000 years, the 2 millennia between Noah’s flood and the Tower of Babel. The account says there was about 2000 pigs,1 so the exact number of years from Noah’s flood to this event is likely close, but not exactly, 2000 years.
The Tower of Babel is one of the times when Jesus came down in person before his birth 2000 years ago. His goal at the tower of Babel was to break up a large group of people who were at the time attempting to build a city and a tower that reached into heaven. What he wanted mankind doing at that point in history was spreading out across the world, forming many countries. The way he did it at the Tower of Babel was to confuse the languages of the people so they would stop working together. This also forced the people to congregate in smaller groups, today called countries.
That linkage allows a complete explanation of the rest of this parable.
At the Tower of Babel, the people building the tower did not want to be sent out over the whole world. Here the demon does not want to be forced out of the country. These two thoughts are the same, only differs by the scale of the perspective.
The scattering of the people at the time of the Tower of Babel lead to what the Bible calls the Gentile nations. The pig is often a symbol of Gentiles. The Seas are also a symbol of the gentile peoples, or peoples around the world. When Jesus gives the demons permission to leave this man and enter the pigs and thus enter the sea, the parable is exactly following the historical account of the Tower of Babel.
When the people in the area learn of what has happened with the demoniac and the 2000 pigs, they beg Jesus to leave their area. They are asking Jesus to do what the demon did not want. Likely the people of the area are possessed by the same spirit, only without the same overt problems exhibited by the demoniac.
At the end of the parable the man does want to leave his country, confirming he has been set free of the demon. In the historical account of Babel Jesus had come down to earth. Everyone saved knows they will eventually leave the planet, but not until it is the right time. Before leaving with Jesus eventually we must go and tell others about our encounters with him. Eventually we will get in the boat with him and leave for the New Jerusalem. Until then...
Jesus commanded the man to go and share with others how he had been delivered. In did this in the area of the Decapolis. This was a region along the south east shore of the Sea of Galilee, in the tribal allotment that was once the eastern half of the tribe of Manasseh. Manasseh, the western half, had also controlled the city of Samaria, which was the capital of the northern kingdom of ancient Israel. The northern kingdom was known as "The Ten" because when civil war divided the kingdom after Solomon’s reign 10 tribes who’s capital was eventually Samaria were separated from two tribes who’s capital was Jerusalem. Everywhere in scripture that "Ten" is used the prophetic story is pointing in some way at the northern kingdom of ancient Israel.
The northern kingdom was deported at the time of the Assyrian invasion, when they lost control of their historical tribal lands. Their exact locations are considered a mystery by the majority of Christians. The Bible explains that the first location where the Assyrians hauled the northerners was Halah, Gozan, Hara, the Habor River area and the cities of the Medes. This last location is important because 200 years after the Assyrian deportation the Medes controlled ancient Babylon and would eventually supply the Babylonian Kings.
One of the most famous stories in the Bible is Nebuchadnezzar’s dream of a statue. That statue describes the general flow of human history from that point and ends with a period before the return of Jesus when the world is depicted as being in a season of "Ten Toes" The Ten are still the northern kingdom’s 10, but have now spread around the whole world.
This parable connects the Ten Cities to the story of the Tower of Babel, itself a story involving the entire world. The linkage is deliberate, explaining that the Lost Tribes are linked directly to the entire world.
1 Mark 5:13