Christ is the all-inclusive and all-extensive One (Eph. 1:23b). According to Ephesians 1:23, Christ is the One who fills all in all; hence, He is all-extensive. As the all-extensive One, surely He is all-inclusive.
This all-inclusive, all-extensive Christ is the only begotten Son of God from eternity (John 3:16a; 17:24b), and the firstborn Son of God from His resurrection in humanity (Rom. 8:29b; Acts 13:33). Christ as the Son of God has two statuses: the only begotten Son of God and the firstborn Son of God. Most Christians have no realization concerning this, and some may even say that this is heresy. However, this is not heresy, for it is clearly mentioned in John 3:16, which says that Christ is the only begotten Son of God, and in Romans 8:29, which says that He is God's firstborn Son among many brothers.
As the Son given, Christ is called "the Father of Eternity" (Isa. 9:6); hence, He is one with the Father (John 10:30; 14:8-10). We can say that Christ is both the Father and the Son because He is all-inclusive. If He were only the Son and not the Father, He would not be all-inclusive.
In His resurrection Christ became the life-giving Spirit (1 Cor. 15:45b). He is not only the Son and the Father; eventually, He became the life-giving Spirit as well. Hence, He is the Spirit and the Lord Spirit (2 Cor. 3:17-18).
In 1964 shortly after I came to the United States, a dear friend warned me, saying that although this kind of teaching is in the Bible, Christianity would not accept it. So he advised me to put this teaching aside. In response, I told this brother that since this teaching is in the Bible, he should give me the liberty to speak this matter as the Lord had led me to do. I told him that if I could not speak on Christ as the Spirit, I would have nothing to speak. Now, twenty-six years later, it is common to hear the saints in the Lord's recovery speak of Christ being the Spirit. In the Lord's table meetings, many of the saints praise the Lord not only for dying for us on the cross and resurrecting from the dead, but also for being the life-giving Spirit who indwells us. If we could praise the Lord only for dying for us on the cross, for resurrecting, and for now being seated in the heavens, our feeling would not be so sweet, for Christ would be far away from us. But, hallelujah, today the crucified and resurrected One has become a life-giving Spirit indwelling us! No one can deny this. This is an important item in the New Testament. It is also a major item in the Lord's recovery.