What does John 4:4 mean?

Samaria lies directly between Jerusalem and Galilee. To make the shortest possible trip between the two, a person could simply pass through Samaritan territory on their way from the city. However, most Jews loathed Samaritans. The preferred route was to cross the Jordan river into Perea, avoiding contact with the despised tribe. And yet, this verse says Jesus "had to pass through" this territory.

Samaritans were half-Jewish and half-Gentile, both ethnically and religiously. This made them unclean, hated outcasts in the eyes of the common Israelite (John 4:9). Why would Jesus be obligated to go through this region if there were other options? In short, Jesus is not only submissive to God's timing (John 2:4), but also to His will.

Travelling through Samaria provides Jesus an opportunity to speak with the woman at the well (John 4:7–9). This leads to more ministry opportunities, in speaking to the Samaritans of her town (John 4:40–41). Jesus also uses this as an object lesson for His disciples (John 4:35). In fact, what Jesus does on this short journey foreshadows His command to the disciples at His ascension. In this part of the gospel of John, Jesus travels from Jerusalem, through Judea, into Samaria, and is proclaimed by the Samaritans as the "Savior of the world" (John 4:42). At His ascension, in Acts 1:8, Jesus commands His disciples to carry His message "in Jerusalem and in all Judea and Samaria, and to the end of the earth."