Door in the Wall, The

Ever since he can remember, Robin, child of Sir John de Bureford, has been told what is expected of him as the son of a nobleman. He must learn the ways of knighthood. But Robin’s destiny is changed suddenly when he falls ill and loses the use of his legs. Fearing a plague, his servants abandon him, and Robin is left alone.
A monk named Brother Luke rescues Robin and takes him to the hospice of St. Mark’s, where he is taught woodcarving and patience and strength. Says Brother Luke, “Thou hast only to follow the wall far enough and there will be a door in it.”
Robin learns soon enough what Brother Luke means. When the great castle of Lindsay is in danger, Robin discovers that there is more than one way to serve his king.