The rapid growth of the early church took place because people with zeal and vision went everywhere preaching the gospel. We need not expect a harvest without first sowing the seed of the kingdom. God has put into the hands of his people the duty to teach other people. The Holy Spirit will not directly convert sinners, but his word is so powerful that when one person teaches another who believes and obeys it, that person is saved. There are not enough people teaching others.
Laborers are few.
We have fewer missionaries around the world today than we have had in the last several years. It is increasingly difficult for missionaries to get support to go. Churches don't want to be bothered with the added problems connected with foreign work. Friends, we don't have a choice about whether we engage in world evangelism. This is the reason the church exists.