Everything in us tries to restore homeostasis when it's upset. Can we be balanced with only the physical and not the spiritual, or are these two sides of the equation? What about the people who prefer to be unbalanced - is that natural or an aberration? I'm thinking of people who require constant or extreme stimulation.
If we're totally physical, if even our spiritual experiences are generated from chemical reactions in the brain, does that mean spiritual life is part of necessary human homeostasis? Does it require an "intake" of spirit from God? No one would know it had been missing until it's searched out or given.
Long ago, I read about a man in jail for crimes against children, the man tried to castrate himself but they stopped him. What about Jesus saying cut off the hand that "offends" you if you can't control it? why do people so sweetly condescendingly say, "Well we know that's not what he really meant. It isn't LITERAL." Then often those same people take the more pleasing, understandable parts literally. If we're physical, including the spiritual aspects (some believe that, some don't), why shouldn't we cut off unruly, out of control parts? If our thoughts come from our physical makeup, why not change the physical?
Obviously, our body parts are not acting on their own, they are under control of our thoughts. People who "can't" control their thoughts would have to cut off their heads! Maybe that's why cutting off the part that offends you is not considered literal. But if you're missing a hand, you can't do the wrong things you kept doing. Maybe it WOULD work. The man who tried to castrate himself, well, aren't men's thoughts and impulses from the parts he was trying to get rid of? The perversion of these impulses in this man didn't come from his natural body, but without the body, he could no longer commit the heinous crimes he had been committing.
I don't actually condone mutilation! But Jesus said it. Perhaps it's pointing out how important it is to keep our thoughts under control. If we can't or won't, the only option left is to make ourselves UNABLE to do wrong things. Would that really help with the thoughts? Would fear of even more severe action add the needed impetus to control where we allow our minds to wander?