Friedrich Schiller, Don Carlos, act I, scene iv, Don Carlos, Mary Stuart, trans. R. D. Boylan and Joseph Mellish, p. 30 (1902). The Marquis is speaking. "Great spirits suffer patiently" is the translation in Friedrich Schiller, Plays, ed. Walter Hinderer, Don Carlos trans. A. Leslie and Jeanne R. Willson, p. 124 (1983).https://en.wikiquote.org/wiki/Silence