Bones solid as rock

C.S. Lewis writes:

I have stood by the bedside of a woman [i.e. Joy Davidman] whose thighbone was eaten through with cancer and who had thriving colonies of the disease in many other bones, as well. It took three people to move her in bed. The doctors predicted a few months of life; the nurses (who often know better), a few weeks. A good man [Peter Bide] laid his hands on her and prayed. A year later the patient was walking (uphill, too, through rough woodland) and the man who took the last X-ray photos was saying, “These bones are as solid as rock. It’s miraculous.”