Regarding the origins of the Great Revival in Korea at the turn of the 20th century, during a massive outbreak of cholera, a historian writes:
“At the same time an epidemic of cholera in Seoul brought reports of the indefatigable toil of the Christian missionaries for the sick and dying there, how they performed duties from which the bravest Koreans often shrank, exposing themselves without stint, and saving hundreds of lives. ‘All these recoveries made no little stir in the city. Proclamations were posted on the walls telling the people there was no need for them to die when they might go to the Christian hospitals and live. People who watched the missionaries working over the sick night after night reportedly said to each other, “How these foreigners love us! Would we do as much for one of our own kin as they do for strangers?”
When Horace Underwood was seen hurrying along the road in the twilight, some of the Koreans remarked, “There goes the Jesus man: he works all day and all night with the sick without resting.”
“Why does he do it?” said another.
“Because he loves us,” was the reply.'”
-Palmer, Korea and Christianity, 1967, citing Moffett, The Christians of Korea, 1962.