One popular philosophical argument in favor of religion and the existence of souls (substance dualism) is the argument based on the impossibility of accepting at the same time the existence of personhood as we ordinarily think of it and the physical grounding of the mind.
The problem that gives rise to the argument is that we know that what we experience as our free choices seems to have actual physical effects in that electric signals are sent down the nerves. But then the question becomes how these supposedly free choices (that can’t be purely physical because they wouldn’t in that case be free) may have physical consequences but be grounded in physical phenomena but at the same time not be reducible to them. It is the combination of these three features that makes the grounding of free will in physicalism problematic. Physicists claim that physical phenomena are deterministic from which they deduce that the phenomena that are not reducible to physical phenomena may not have physical effects, unless some supernatural mechanism is at work. So it seems that one may not have freedom of choice and physical grounding at the same time.
It seems that the argument is damning until we ask the same question about chemical phenomena that also have physical effects.
There is a good case to be made that chemical phenomena are not reducible to the micro-physical ones (see, e. g. this article by the Nobel Prize winning chemist Roald Hoffmann). Yet, clearly, many chemical phenomena have physical effects and are at the same time grounded in physical phenomena (or, in the language of the modern philosophy, supervene on them). There is nothing that would make mental phenomena like choices in principle different in this sense. Thus, the dichotomy between the physical grounding of the mind and the existence of free will seems to be a false one.