Christian psychology is the study of man’s soul and how it stands in relationship to God. This study was the cause of heresy and conflict within the medieval churches. The dogmas developed in this field at that time had their origins basically in either Greek philosophy or theology. These positions were antithetical, yet attempts to compromise were constant.

A Greek philosopher such as Aristotle would define the soul as follows: It is the vital principle of all living things. That is, firstly, that the soul is life for the body. The body is merely a material shell for the soul. The soul is the cause of every bodily act, the principle of life. Secondly, all living things possess this principle of life in one degree or another. For example, all plants possess a soul. It is a nutritive one. It is responsible for all biological processes in plants. All animals also possess a nutritive soul as plants, yet animals are more advanced because they also have a sensitive soul. It is responsible for the powers of sensations, desires, and local motions. All men possess a nutritive and a sensitive soul as animals. However, man is more advanced; he possesses a rational soul. If man were to lose his reason he would become an animal regardless of his human form. And if man were to lose his reason, sensation, desire, and local motion; which is conceivable, he would be nothing more than a vegetable.

To understand what Greek philosophy meant when it talked about reason, which is that quality in man that separates him from the animal; the following illustration may prove useful. Imagine a jig-saw puzzle which is put together but is completely blank. Each piece of the puzzle represents reason for an individual man before he lives on earth. When a man comes into being, reason (a piece of the puzzle) is placed within the human form. By means of earthly experiences reason is developed (the piece of the puzzle is painted). Thus, when man dies the human form returns to the dust from whence it came, and reason returns to its origin (the piece is placed back into its proper place within the puzzle). (This process continues until all the pieces are painted and a beautiful picture results.)

This so called jig-saw puzzle they said is God; Who is reason, good, beauty, eternal,… Each man is in part therefore God.

Their theories of the composition of man’s soul and the origin of man’s reason mean this: All men are and do good. If a man does a wrong act it is done either under external compulsion, the working of the sensitive soul – that part of animal in all of us – over-against the working of reason, or it is done out of ignorance, misunderstanding the circumstances.

Good is the general opinion formed by men. It is the right thing to do according to the requirements of the situation. One starts to do good as an act of his free will, but this act of choosing later becomes established as a habit in man. Man just cannot help but to do good because it is part of his nature.

For a criticism of Greek philosophy in the realm of psychology I will use the position of Augustine. Although Augustine did not develop a system of psychology, he did write and develop thought from the Scriptures to fight against the views of man’s goodness which were basically Greek. Therefore, from these writings one may deduce properly a psychology.

First, one of the reasons why Augustine did not develop a system of psychology is that the Scriptures is not a text book on psychology. The Scriptures are the Word of Christ. The position of man is incidental, the object of God’s salvation through Christ. Man has no part in his salvation, and because of this the Scriptures are not of man, but of Christ. Yet, man as the object of salvation is mentioned in Scripture, and for this reason Augustine knew and can know of man’s soul and how it stands in relationship to God.

Augustine did not concern himself with the question of the composition of the soul. The soul was created by God when He breathes into man the breath of life. After man fell he lost the image of God and became totally corrupt. This original corruption and pollution was passed to all men. This was done, in Augustine’s view, by the passing of the soul through conception. (One must keep in mind that Augustine adopted this view of the passing on of the soul as a means of explanation for the passing of original sin and not vice versa.)

Before we look at Augustine’s view of reason, a distinction of the term good must be made. Good is not doing what is right according to the circumstance, situation ethics, nor is it some intrinsic beauty within man like we have seen. Rather, this is good: “Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment. And the second is like unto it, thou shalt love thy neighbour as thyself” (Matt. 22:37-39).

Reason cannot and does not seek after good. It cannot because reason as a power of the soul is wholly polluted by sin. It does not because reason uses its power to “change the glory of the incorruptible God into an image made like to corruptible man” (Romans 1:23). This is a willful act. It is not done out of ignorance. Philosophical psychologists attempt to justify their sins against God by doing this. The philosophers after Augustine knew this, and they knew the writings that testified to this, yet the battle continued. Does man have within his soul some ability to do good? Does man sin in ignorance and therefore is not responsible before God?