" We are familiar with the thought that our bodies are like machines, needing the right routine of food, rest and exercise if they are to run efficiently, and liable, if filled up with the wrong fuel—alcohol, drugs, poison—to lose their power of healthy functioning and ultimately to “seize up” entirely in physical death. What we are, perhaps, slower to grasp is that God wishes us to think of our souls in a similar way. As rational persons, we were made to bear God’s moral image—that is, our souls were made to “run” on the practice of worship, law-keeping, truthfulness, honesty, discipline, self-control, and service to God and our fellows. If we abandon these practices, not only do we incur guilt before God; we also progressively destroy our own souls. Conscience atrophies, the sense of shame dries up, one’s capacity for truthfulness, loyalty and honesty is eaten away, one’s character disintegrates. One not only becomes desperately miserable; one is steadily being dehumanized. This is one aspect of spiritual death. Richard Baxter was right to formulate the alternatives as “A Saint—or a Brute”: that, ultimately, is the only choice, and everyone, sooner or later, consciously or unconsciously opts for one or the other. "
― J.I. Packer , Knowing God