What does Matthew 15:29 mean?

In the preceding passage, Jesus was in the thoroughly Gentile region of Tyre and Sidon with His disciples. He left Israel for a time to withdraw from the crowds and the religious leaders (Matthew 15:21). Now He returns to Israel. Matthew simply says that Jesus went on and walked by the Sea of Galilee. We know from Mark's additional details that He traveled north through Sidon, returning south along the east side of the Sea of Galilee to the region of the Decapolis.

Jesus and the disciples may have taken that long way around to keep out of the territory controlled by Herod the tetrarch, which included Galilee and land to the east of the Jordan River. Perhaps they did so to avoid conflict with the religious leaders. Or maybe they were simply avoiding the ever-present crowds in Galilee.

It would have also brought Jesus back near to the place where He had sent some demons into a herd of pigs (Matthew 8:28–34) and kept Him in a Gentile region instead of a Jewish area.

Jesus finds an elevated spot on a "mountain"—what most other cultures would think of as a high hill—and sits there. Then the crowds find Him.