Man's spirit is the noblest part of man; it dwells in man's innermost part. The body is the lowest and remains outside. The soul dwells between the spirit and the body and is the medium of the two. The body is the outer shell of the soul, while the soul is the outer shell of the spirit. When the spirit tries to control the body, it has to do so with the help of the intermediary soul. Before man fell, it was the spirit (through the soul) that controlled the whole being. When the spirit wanted to do something, it communicated to the soul, and the soul activated the body to follow the order of the spirit. This is what it means for the soul to be the medium.

The soul is potentially the strongest part because both the spirit and the body are incorporated into it, take it as their personality, and are affected by it. But in the beginning, man had not sinned, and the power of the soul was fully under the control of the spirit. Hence, the power of the soul was the power of the spirit. The spirit could not drive the body by itself; it had to do so through the soul. We can see this from Luke 1:46-47: "My soul magnifies [present tense] the Lord, and my spirit has exulted [perfect tense] in God my Savior." Here we see the change in tense according to the original language, which indicates that the spirit must first exult before the soul can magnify the Lord. The spirit first communicates the exultation to the soul, then the soul expresses this exultation through the organs of the body.

In conclusion, the soul is the seat of personality; man's will, intellect, and emotion all lie in the soul. The spirit is the part with which man communicates with the spiritual realm. The body is the part with which man communicates with the physical realm. The soul is in the middle of these two parts. It exercises its judgment to determine if the spiritual realm is to rule or if the physical realm is to rule. Sometimes the soul rules through its intellect and senses; when that happens, the psychological world rules. Unless the soul yields its rule to the spirit, the spirit cannot rule. Hence, the soul has to authorize the spirit to rule before the latter can rule over the soul and the whole body. The reason for this is that the soul is the origin of man's personality.

The soul is the master of a person because man's will is part of the soul. When the spirit controls the whole being, it is because the soul has yielded itself and has taken a lower position. If the soul rebels, the spirit will not have the power to control it. This is the meaning of "free will" in man. Man has the absolute right to make his own decisions. He is not a machine which turns according to God's will. He has his own faculty of deliberation. He can choose to obey God's will, and he can choose to oppose God's will and to follow the devil's will. According to God's arrangement, the spirit should be the highest part and should control the whole being. Yet the main part of man's personality, the will, is of the soul. Man's will (soul) has the power to choose to let the spirit rule, to let the body rule, or to let the self rule. Because the soul is so powerful, the Bible calls it "a living soul."