According to an ancient Persian legend, quoted by E. F. Benson in The Challoners, a lover knocked one day at the door of his beloved and the beloved said, “Who is that?” He replied, “It is I,” and the one on the inside said, “There is not room for two.” So he went away, came back after a year, and knocked again. And again from the inside the voice said, “Who is that?” But this time he said, “It is thou.” So the door was opened and he went in.