What does Luke 8:34 mean?

The pig herders have a problem. They watched helplessly as thousands of their animals (Mark 5:13) suddenly ran down the steep hill and into the Sea of Galilee where they all drowned (Luke 8:33). The men don't own the pigs; they're just tending them. They need to spread the word, not only because it's an incredible story, but because they need corroboration that they're not responsible for the loss of the herd. Matthew says that the herdsmen told the people in the city "everything, especially what had happened to the demon-possessed men" (Matthew 8:33).

Again, Westerners who like detail are flummoxed by the lack of information on their exact location. Those details are irrelevant to Luke's purposes. All we can say is they are close to the east coast of the Sea of Galilee and near to a city; the herders can run there and witnesses can run back in a fairly short amount of time (Matthew 8:33–34).

When the people arrive, they don't mention the pigs. They're much more interested in the fact that the man who had been possessed by a legion of demons is "sitting at the feet of Jesus, clothed and in his right mind" (Luke 8:35). Jesus seems to be using the pigs so that everyone in the district can see that this man has been rescued. When He returns to Galilee, He will ask who had touched His robe to publicly praise a woman's faith and declare to the crowd that she is clean (Luke 8:45–48).