This answers the question of how it is to be done, but it is necessary now to understand that this method can accomplish its purpose only when the followers practice what they learn.
It did not matter how small the group was to start with so long as they reproduced and taught their disciples to reproduce. This was the way his church was to win—through the dedicated lives of those who knew the Savior so well that his Spirit and method constrained them to tell others. As simple as it may seem, this was the way the gospel would conquer. He had no other plan.
from The Master Plan of Evangelism
By Robert Coleman