I'm reminded of the man wih legions of demons having been cast out by Jesus. When the countryside of Gerasenes saw the pigs drown, they told Jesus to go. The man who was sitting clothed in his right mind wanted to follow Jesus, and Jesus told him to go back to his house and tell them how the Lord God had mercy on him.
It's about witnessing, and witnessing to those who you are accessible to, what YOU can do. Jesus didn't tell him to go to the ends of the earth - that would be a project for future groups and families of Christians. Jesus told the demoniac to witness to his household, because the whole countryside told Jesus to go. The man ended up going to the city and proclaiming what great things Jesus had done for him.