How do you reconcile materialism with the Christian perspective of the soul?

Christians do believe that the universe is fundamentally governed by consistent natural laws which were instituted by God. The consistent and reproducible nature of these laws allows us to pursue scientific exploration, research and development. These laws are in accordance with His wisdom and reflect His own nature and His glory. In respect to the existence of these laws there is no conflict with the materialistic view.

On the other hand, most Christian denominations also believe that God alone is able to break these laws, commonly called a miracle, while some denominations do not believe in the same. You cannot have a miracle without materialistic laws. A miracle in that sense would not be a miracle if there were not otherwise unbreakable laws in the first place. This is where a purely materialistic and the Christian view diverge. The difference between the two views is not so much whether God is capable of breaking natural laws, but whether he exists.

Most, if not all Christian denominations also believe that God is able to work miracles or interact supernaturally with the Creation in a way that does not break natural law, usually based on a form of either foreknowledge or predestination. As an example, you may pray for something, and what you prayed for may come to pass using purely materialistic mechanics and explanation - nevertheless, on God's level, it was His arrangement.

Regarding the mind, you will find varying views from denomination to denomination, and from person to person. The predominant view (and variations of the same) is that the mind consists of more than just a the physically determined mind, but also a spirit (some again distinguish between spirit and soul), and that these affect each other, and have some form of relationship and interaction which results in our intellect and free will.

With recent developments in psychology and psychiatry, scientists have begun to think humans are entirely mechanical beings, that everything in us is just determined by electro-chemical processes.

I have a background that relates to one of these fields, and I agree that the medical scientific community predominantly strives for purely naturalistic/materialistic explanations. At the same time, this is not always successful. To give an example, there are various naturalistic theories, but as per textbook no scientific explanations why some people with a mental illness 'hear voices'. They can measure the brain activity of the voice being heard, but no brain activity that would be conclusively responsible for "generating" the voices. Different theories exist, and which of those an individual accepts as plausible may be based on their own learning towards materialistic/supernatural beliefs.

Christianity and Materialism

Generally speaking Christianity is not reconcilable with materialism. There are two very simple syllogisms that illustrate why. The first is as follows:

1. No one who believes in an afterlife believes in materialism
2. Christians believe in an afterlife
3. Therefore Christians do not believe in materialism

If the human person persists after death, apart from their material body, then clearly materialism is false. Granted, there are a small number of Christians who have tried to circumvent this argument by pointing to the Christian belief in the bodily resurrection at the end of time. This final resurrection is a material reality, and so is not intrinsically incompatible with materialism in the way that a state of immaterial existence would be. Nevertheless, the common view is that the "intermediate state"--the state between death and resurrection--is a time of immaterial existence for the human person, and that the persisting identity between the dying person and the resurrected person requires an intermediate state.

The second syllogism is even stronger:

1. If materialism is true then there are no immaterial entities
2. God is an immaterial entity
3. Therefore Christians, because they believe in God, believe materialism to be false

Anyone who believes in God believes materialism to be false, for if God exists then materialism is false. The same argument holds for angels. In the end Christianity just isn't compatible with materialism.

The Nature of Materialism

Materialism is a metaphysical hypothesis, not a scientific hypothesis, so it can't be proved or disproved by science. Since the modern period the philosophical problems related to the tension between materialists and immaterialists have included things like the hard problem of consciousness, mind-body dualism, and the problem of identity. Science hasn't contributed to these debates in any substantial way.

Materialism itself is not a contemporary phenomenon and is actually quite old. Some of the oldest systematic expositions we are aware of come from ancient Greece and India, and usually saw reality as reducible to small material particles, hence the common name, "Atomists." Well known materialists in the modern period include Hobbes, Diderot, Feuerbach, and Marx. None of these thinkers grounded their thought in science in any special way. (Wikipedia)

Obviously most religions reject materialism, but materialism is also rejected by Platonists, Aristotelians, Manicheans, Thomists, Cartesians, Leibnizians, and Husserlians just to name a few. Though materialism's popularity has grown of late, it is just one metaphysical position among many.

Mathematics is not material. It is a set of immaterial ideas.

Computers are material. Computer software, as an idea represented as ones and zeroes, is an immaterial construct.

A book is material, but the ideas it contains are not material. The ink is material, the paper material, but the arrangement of ink on paper was decided by an intelligent being who expressed immaterial ideas in a material form.

We are God's ideas. His immaterial, invisible properties are written onto the matter of this world, including our bodies.

Because of this, Job in chapter 28 of his book can search all creation and say that he could not find widsom anywhere in it, while God in chapters 38-41 could at the same time point to the material world and say that it displayed his wisdom and glory.