What does Luke 8:26 mean?

Jesus and the disciples have survived a violent storm at night on the Sea of Galilee. Now, they land on the eastern shore. It is unclear exactly where this is, a task made more difficult because manuscripts of the synoptic Gospels use three different terms to identify the locals.

"Gerasenes" are people who live in Gerasa, in modern-day Jerash, Jordan, southeast of the Sea of Galilee. Most translations of Matthew and some of Mark and Luke use "Gadarenes," referring to residents of Gadara, a Greek city much closer southeast from the southern tip of the Sea. Some translations of Matthew use "Gergesenes," referring to Gergesa, a region in Decapolis, directly across the Sea of Galilee from the district of Galilee. Geographically, Gergesa makes the most sense, but the location was not considered until Origen thought it a good option in the early- to mid-third century. Gerasa is too far away, but it's worth noting that "Gergesa" turns to "Gerasa" with a slight transcription error. In other words, the difference in the records is likely a simple spelling error by copyists. What's not in doubt is that the boat landed on the other side of the Sea of Galilee in a Gentile region.

The broader location becomes more significant somewhat later. After Jesus releases the man from possession by a legion of demons, He tells the man to share what God has done for him throughout the region. He does so to great effect. After Jesus freed the man, the locals insist Jesus return to the boat and His side of the Sea. Sometime later, when Jesus returns to the area, He is so welcomed that four thousand people come to hear Him speak (Mark 7:31—8:10).