Matthew 10:14-16

And if anyone doesn’t listen to you and rejects your message, when you leave that house or town, shake the dust off your feet. Mark my words, on the day of judgment the wicked people who lived in the land of Sodom and Gomorrah will have a lesser degree of judgment than the city that rejects you, for the people of Sodom and Gomorrah did not have the opportunity that was given to them! Now, remember, it is I who sends you out, even though you feel vulnerable as lambs going into a pack of wolves. So be as shrewd as snakes yet as harmless as doves.”