Still Looking for the Door in the Wall
[Brother Luke to the 10-year-old Robin, whose legs have been paralyzed by illness and whom the friar has come to take to the convent of St. Mark's so that he will have a place to live while his parents are away]: "...Dost remember the long wall that is about the garden of thy father's house?"
"Yes," said Robin, "of course. Why?"
"Dost remember, too, the wall about the Tower or any other wall?" Robin nodded. "Have they not all a door somewhere?"
"Yes," said Robin again.
"Always remember that," said the friar. "Thou hast only to follow the wall far enough and there will be a door in it."
"I will remember," Robin promised, but he wasn't sure that he knew what Brother Luke meant to say.
--Marguerite de Angeli, The Door in the Wall (New York: Doubleday, 1949), p. 16.
[NB: I first read this book when I was in fourth or fifth grade. It, more than anything else, is probably the reason that I became a medieval historian. I'm still looking for my door.]