Luke 9:5
And whosoever will not receive you, when ye go out of that city, shake off the very dust from your feet for a testimony against them. And whosoever will not receive you, when ye go out of that city, shake off the very dust from your feet for a testimony against them.
Luke 9:5 belongs to Jesus' first instructions in sending out the twelve as His representatives to preach and labor alone. The twelve had accompanied Him on foot through Galilee, shared His toils and hardships, listened to His discourses, and walked and talked with Him, learning from daily instruction and example how to work for the elevation of humanity. That learning came by attending Him among the multitudes, arranging the people, bringing the afflicted to Him, watching for interested hearers, explaining the Scriptures, and teaching what they had learned. Though still needing much instruction, great patience and tenderness, and freeing from fear of the rabbis and bondage to tradition by having Scripture set before them in contrast with tradition, they were sent while He was still personally with them to point out their errors and counsel and correct them, so that when separated from Him every look and tone and word would return to them in conflict with the enemies of the gospel.
The twelve were given the same initial directions later given to the seventy, showing that the mission was carried out according to a shared plan. Both groups were sent under Jesus' direction to work as He did and announce that God's kingdom had come near. Their mission joins preaching the kingdom of God, teaching, and healing the sick into one blended and inseparable work, not to be separated. It was appointed despite satanic opposition, with divine power displayed against that opposition. That united preaching and healing is the work now given to God's people in fulfillment of the Scriptures, which everyone should study to see how they harmonize and to understand it.
The verse gives the sign for a city or town that will not receive the disciples and their message: when going out from it, they are to shake its very dust from their feet for a testimony against it. The mission is thus connected with people's receiving or rejecting the message and the messenger. The act warns that the gospel message cannot be rejected with impunity, for the city that refuses to hear faces a more severe judgment than Sodom and Gomorrah. When people in a place refuse and persecute the messengers, they are to leave that place and go elsewhere. The same counsel applies when God's people cannot influence a city given to pride and idolatry or fully do God's will there, in which case they may move to towns, villages, or cities with less objectionable surroundings. It also applies to a worker whose health is failing under labor in an unhealthy climate, who should be able to leave, rest, or serve where health can be preserved.