From Romans to the seven epistles in the book of Revelation, the life-giving Spirit, spoken of in 1 Corinthians 15:45, is the general subject of all the New Testament Epistles. In the Gospels the Lord Jesus is presented as the Word who became flesh, while in the Epistles He is presented as the One who became the life-giving Spirit in resurrection for us to receive, experience, and enjoy. In The Spirit in the Epistles Witness Lee speaks of the believers being one spirit with the Lord, that is, of the mingling of the divine Spirit with our regenerated human spirit. Since the Spirit is the essence of the revelation in the Epistles, Witness Lee also emphasizes our practical need to take Christ as life by turning to the indwelling Spirit, by setting our mind on the spirit, and by living and walking in the spirit that we may live in the Lord, who is the Spirit.