Use of the terms “soul” and “spirit” in the Bible is very complex. Often in the New Testament, they are used synonymously to refer to the immaterial part of man; at other times, they are used with fine distinctions. In those cases, the term “soul” seems to refer to man’s more basic psychological functions as he interacts with the world, while “spirit” seems to focus on man’s relationship with God. In the Old Testament, “soul” is sometimes used to refer to man in his totality.
Theologians struggle with the question of whether man is made up of two parts, namely body and soul/spirit, or three parts, namely body, soul and spirit. The latter position has been popularized through the teaching of many Christian psychologists and teachers, since it furnishes such a handy way to distinguish between man’s material nature, his psychological structure, and his spiritual relationship to God.
Illustrations from the Bible would be as follows: In Genesis 2:7 the Hebrew word for soul is used in reference to man in his totality as created by God. A situation in the new Testament where soul and spirit appear to be used synonymously is Luke 1:46-47. An instance where soul and spirit (used as adjectives) seem to be in contrast, soul referring to man’s lower psychological functions and spirit to man’s higher spiritual function, is 1 Corinthians 2:14-3:4.