Go ye therefore, and teach all nations.
Evangelism is simply the telling of the good news to the world.
This is the central task of the church. The major undertaking of the church is, therefore, the evangelization of all the world. This means that Christianity is a missionary religion, and it has been so from its beginning. By its very nature it has an expansiveness that nothing can restrain. Jesus knew that if He could impart His message to a few, they would tell others who would in turn bring others into the fold.