23. The rules laid out in verses 23–27 constitute an invaluable safeguard for our Christian lives. Since we are attacked at every point, every possible place where sin may gain a foothold has to be guarded against—the heart, the mouth, the eyes, the feet. First the heart, man’s citadel, the center of his dearest treasure. It is frightening to think about its many assailants. Let it be guarded carefully. Never let the guard sleep at his post (Deuteronomy 4:9). The heart must be known, so that it may