Trichotomy is the view that man is composed of three individual parts. For Calvary Chapel and the Word of Faith movement, this corresponds to a separate spirit, soul, and body in man. The proponents of this view often draw further analogies between the Holy Trinity and the "trinity in man".
Chuck Smith said the following:
But because God, you see is a superior Trinity, Father , Son and Spirit. I am an inferior Trinity, spirit , soul and body. I meet God in the realm of the spirit. And so God's Spirit bears witness with my spirit that I am a son of God. Tape 5185
Brian Onken of CRI wrote an excellent article called "Dangers of the 'Trinity' in Man," published in the CRI Forward 8, 4 (Winter 1986):26-28. The article exposes the dangers of making a sharp separation between the mind and the spirit..
In his book, Answers for Today, Chuck Smith wrote:
When God created man and placed him upon the earth, He created him with his spirit uppermost. Man was spirit, soul, and body. Basically a spiritual being, man was created in fellowship with God within the government of light and life.
In the book, The Answer for Today, Volume 2, Chuck Smith wrote:
However, the Bible teaches that man is more than body. It teaches that man is a soul and a spirit.
These are problematic at best. For a great discussion, see J. Oliver Buswell's Systematic Theology, in the section on dichotomy vs. trichotomy.
The trichotomy is drawn from the following Bible verse:
1 Th 5:23 And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ.
This view leads its adherents to believe that they have a separate soul and body. In of the more extreme cases followers of this view go so far as to teach that it is possible that a persons soul may be lost, but their spirit may be saved.
In contrast to trichotomy, the view accepted by most scholars is that man is dichotomous, or consists of two parts; a material aspect, and a non-material aspect. The non-material part is called by many different names; soul, spirit, mind, life force, or any of a dozen or more equivalent Scriptural words. These are not separate parts of a person, but are just different words for the different aspects of the non-material aspect of man.
Modern REFORMATION (July / August 1995) has an article by Kim Riddlebarger on Trichotomy that refers to Chuck Smith's view as :
Calvary Chapel founder and pastor, Chuck Smith, is a prime example of one whose trichotomist leanings have produced serious doctrinal and ideological consequences.
...
This is a classic case of the Gnostic impulse establishing a major beachhead in the very heart of Evangelicalism.