Ajahn Sumedho (a Western monk) took a party of Westerners to ‘Wat Pah Nanachat’ (a Thai Forest Monastery) in 1981. He did not know that the Western nun there, Ajahn Chah’s first Western nun, had suddenly converted to a very fundamentalist brand of Christianity just before the group arrived. Ajahn Sumedho was expecting she would inspire the Western lay folk who had travelled all that way to Thailand to meet real committed Buddhist practitioners. Instead the nun went around telling this newly inspired group of Western lay practitioners that Buddhism and Ajahn Chah were the work of the devil himself. Ajahn Sumedho got very upset and went to Ajahn Chah complaining about her, about that she was wrong and that Ajahn Chah should stop her immediately and get rid of her as soon as possible.
Instead Ajahn Chah just smiled and said: “Well, Sumedho, maybe she is right.”
[This little story is mentioned in several places, including “The Life and Teachings of Ajahn Chah: Remembrances of His Western Students”, which you can find here.]