Gerald Moore (1899-1987), The Unashamed Accompanist
, rev. ed. (London: Julia MacRae, 1984), p. 35:
Most unfortunate results will attend the accompanist who does not know what he is playing about — what the singer is singing about. A young friend of mine was playing the accompaniment to me one day of Wolf's song "Bitt' ihn, O Mutter" (Beg Him, O Mother). This accompaniment is written with Wolf's usual eloquence and urgency, but it was played by this young lady with such viciousness that I ventured to ask her if she knew what "Bitt' ihn, O Mutter" meant. "Of course," she replied. "It means 'O Mother, bite him.'"
Hat tip: Ian Jackson.