Many religions, such as Christianity and Islam, have a long history of sending out missionaries to convert people to their faith. Others, such as Hinduism and Judaism, do not. But what is the most ethical / logical way? Should religions send out missionaries?
Discipleship is at the heart of Christianity. That is how the Christian church became a worldwide church.
The apostles of Jesus were originally chosen in order "that they should be with him, and that he might send them forth to preach” (Mark 3:14,15). Later, after Jesus rose from the dead, he charged the apostles, "Go ye into all the world and preach the gospel to every creature" (Mark 16:15), and, "Go ye therefore and teach all nations" (Matthew 28:19). He plainly told them, "That repentance and remission of sins should be preached in his name, beginning at Jerusalem" (Luke 24:47).
Just before Jesus ascended to heaven He told the apostles, "But ye shall receive power after that the Holy Ghost comes upon you, and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth" (Acts 1:8). The task of the apostles was plain: tell the good news of Jesus Christ to every person on the planet earth.