The popular notion that the first obligation of the church is to spread the gospel to the uttermost parts of the earth is false. Her first obligation is to be spiritually worthy to spread it. Our Lord said “Go ye,” but He also said, “Tarry ye,” and the tarrying had to come before the going. Had the disciples gone forth as missionaries before the day of Pentecost it would have been an overwhelming spiritual disaster, for they could have done no more than make converts after their likeness, and this would have altered for the worse the whole history of the Western world and had consequences throughout the
ages to come.

– AW Tozer –
from Of God and Men, 35-37.