Charles H. Spurgeon on Psalms 38:8

The disquietness of my heart. David felt pains gather about his heart, and then he cried out. The heart is the mark that God principally aims at when a Christian hath turned aside from his upright course; other outward parts he may hit and deeply wound, but this is but to make holes in the heart, where the seat of unsoundness that principally offends him is. The fire which conscience kindles, it may flash forth into the eyes, and tongue, and hands, and make a man look fearfully, speak desperately, and do bloodily, against the body; but the heat of the fire is principally within, in the furnace, in the spirit; it is but some sparkles and flashes only that you see come forth at the lower holes of the furnace, which you behold in the eyes, words, and deeds of such men. Nicholas Lockyer.