The truth is generally of use - while specious theological musings are generally useless - despite how “true” the formulator of such thinks it is.
What do you think you know of a certainty such that mind couldn't possibly be a machine?
You claim that if truth exists then the mind cannot be a machine? One does not logically follow from the other - despite how much you think it does or how many times you repeat it.
Taller people with larger brains tend to have higher intelligence. Do they have a better “spirit” brain or a better “physical” brain?
An arrangement of molecules and cells where cognitive function is achieved has more intrinsic worth (as far as cognitive function) than one where cognitive function cannot be achieved.
Someone who induced brain damage through regular excessive alcohol consumption does suffer a defect in ‘higher order’ brain function. Do they suffer from a “spiritual” defect or a “physical” defect?
When cognitive function is reduced after eating a large meal due to reduced blood flow to the brain - is the person suffering from a “physical” defect or a “spiritual” defect?
There are countless things that are true that aren’t useful. Or, the uselessness of a thing does not affect its truth.
Regarding the intellect, like the will, it’s an aspect of the soul, or “form,” of the body, in the Aristotelean sense. That is, the soul is the organizing principle of the material body. It is a simple spiritual substance —it has no parts.
In life, the soul is united to the body, causing the body to act coherently as an organism. When the soul is separated from the body at death, the body breaks down into its constitutive components —it decomposes.
The difference in bodily functions in the moments before and after death are incrementally different —no different in degree from the incremental bodily changes leading up to death. Yet something radical happens at death. The body ceases to act as a whole —even while components of the body may continue to live for a time.
If the soul is the organizing principle of the body, it is fully integrated with the body, and changes to the body will affect the soul (while not decomposing it), and changes to the soul will affect the body.
Finally, the idea of the soul accounts for the experience of self, which atomistic materialism cannot explain in a noncontradictory manner.