The Spiritual Man is an extensive study of Christ-centered living written by Watchman Nee . “Watchman Nee (1903–1972) was a noted Chinese Bible teacher and Christian leader. He began his preaching ministry while still a university student. From 1923 to 1950 Nee founded 200 churches. Starting as small groups meeting in rented houses, these self-supporting congregations became strong spiritually and grew rapidly, continuing to develop after China’s Cultural Revolution. Nee was arrested on false charges in 1952 and found guilty; he was imprisoned until his death in 1972.” – CLCpublications.org, http://www.watchmannee.org
On online edition includes this chapter which deals explicitly with the nature of man:
SECTION ONE, CHAPTER ONE
AN INTRODUCTION CONCERNING THE SPIRIT, THE SOUL, AND THE BODY
“Most men today consider man as being made up of two parts: the soul and the body. The soul is the invisible part, the psychological part within man, and the body is the visible part, the outward form of man. This is man’s fallen concept. Although there is some ground to it, it is not accurate. Outside of God’s revelation, no ideas in this world are reliable. It is, of course, true that the body is the outward shell of man. But the Bible never mixes the soul with the spirit or considers the two as the same thing. In addition to being different terms, the soul and the spirit are actually two different substances; they are not the same. The Word of God has not divided man into two parts, the soul and the body. Rather, it has divided man into three parts: the spirit, the soul, and the body. First Thessalonians 5:23 says, ‘The God of peace Himself sanctify you wholly, and may your spirit and soul and body be preserved complete.'”
In another blog, I reaffirm that Nee was an orthodox evangelical
https://elcmatters.org/2018/12/14/watchman-nee-an-orthodox-evangelical/
Biblical Psychology 