Our God is the eternal Triune God. In Exodus 3 He unveiled Himself as Jehovah, the One who was, who is, and who always shall be (v. 14). The eternal Triune God, Jehovah, had to be processed through several steps to be a life-giving Spirit. This life-giving Spirit is Christ in resurrection, the pneumatic Christ, the Christ as the embodiment of the Triune God transformed in resurrection to be the consummated Spirit as the ultimate consummation of the Triune God (1 Cor. 15:45b; 2 Cor. 3:17-18; Rev. 22:17a). Two thousand years ago, before incarnation and resurrection, the Triune God had not yet been consummated. He had only divinity, but He did not have humanity. In order to be a God of both divinity and humanity, He had to go through incarnation, death, and resurrection. Through these three major steps of Christ, the Triune God was consummated. The life-giving Spirit is the consummation of the Triune God. Today we have the eternal Triune God, who is Jehovah, as our Immanuel to be with us. He is the life-giving Spirit for us to walk by, not only to express Him and live Him, but also to accomplish His eternal plan, His eternal economy.
To walk by the life-giving Spirit is not to walk by any power, nor by any means, but by the consummated Spirit as the ultimate consummation of the Triune God, a divine person, who is both God and man, having the divine nature and the human nature as well, and living with us in our spirit a life of God mingled with man (2 Tim. 4:22). This consummated Spirit is the Lord, the pneumatic Christ, the Christ in resurrection, who was the complete God as a perfect man, passing through the processes of incarnation, crucifixion, and resurrection to become the life-giving Spirit in order to live in our spirit, not only as a power or a means to strengthen us, to support us, to help us, but also as a complete person of divinity and humanity to be our life that we may live God's divine life mingled with our human life.