John 4:3 He left Judaea, and departed again into Galilee. 4 And he must needs go through Samaria.
The disciples of Jesus looked to Him for leadership. Without His guidance they would have had no notion of what to do or where to go. Jesus had the plan and knew what He was doing. He walked in the light, so those who walked with Him, following His plan, also walked in His light.
When He said he was going through Samaria, some of His disciples may have thought His light had dimmed. We are quick to judge His commands based on our own comfort levels. The Samaritans and Jews were not on friendly terms, and had not been for centuries. In fact, Pilate was removed from Palestine by the Roman authorities because of his mafia-like tactics in dealing with their ongoing feud. Jews had been killed just traveling though Samaria. But Jesus said go, so they went. He was in full control of His Government. He controls it still.
It became clear, after the fact, what Jesus' purpose was in going that way. It has been my experience that it is often only afterward that His motives become visible. Sometimes His purpose is never made visible to us. I guess that's what faith is all about. His purpose was to preach the Gospel to the Samaritans. And that is just what He did.
Jesus’ authority has not withered away with time. He still commands His forces and accomplishes His plans in an organized purposeful way. He leads His disciples where He wants them to go, and He uses them to accomplish His plan. It is wise to walk in His light.