Hudson Taylor's conversation with a new convert name Nyi:
It was he who, talking with Mr. Taylor, unexpectedly raised a question the pain of which was not easily forgotten.
"How long have you had the glad tidings in England?" he asked unsuspectingly.
The young missionary was ashamed to tell him, and vaguely replied that it was several hundreds of years.
"What," exclaimed Nyi in astonishment, "several hundreds of years! Is it possible that you have known about Jesus so long, and only now have come to tell us? My father sought the truth for more than twenty years," he continued sadly, "and died without finding it. Oh, why did you not come sooner?"
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The truth is, that while the missionaries are often roughly treated and persecuted - if no one goes... well, let's follow the reverse logic of Romans 10:13-15.
If no one goes (or is sent), no one will preach. If no one preaches, no one will hear. If no one hears, no one will believe. If no one believes, no one will call on the Lord Jesus. If no one calls on the Lord, no one will be saved.
As Curt Daniel has said, "Those who never hear can never be saved. What an incentive for us to go to them with the Gospel! They who never hear will all go to Hell."