Because of man's reaction, God, who had hired everyone, eventually fired everyone that He might replace everyone with Christ. When everyone and everything is replaced with Christ, Christ becomes everything. For example, He becomes to us both the Shoot of Jehovah and the Fruit of the earth.
In Isaiah, everything is fired, discharged by God, and then the discharging God comes in to replace everything with Christ. This is Paul's concept in Colossians 2:16 and 17: "Let no one therefore judge you in eating and in drinking or in respect of a feast or of a new moon or of Sabbaths, which are a shadow of things to come, but the body is of Christ." Here Paul is telling us that our food and drink, feasts, new moons, and Sabbaths are all shadows of Christ. Christ, therefore, is the replacement of all the things in God's Old Testament economy.
God put all things in place, and then He fired them all. He put all the kings in place, and then He fired them all and made Christ the unique King. However, the kingship of Christ is a corporate kingship; it includes Christ and those who are one with Him. In the same way, the priesthood is a corporate matter: Christ is the High Priest, and we are one with Him. In this way God replaces everything with Christ, and we are joined to Christ. On the one hand, we are fired, and on the other hand, we are not expelled; for Christ comes to live in us, with us, by us, and through us. This is Immanuel replacing everything and being everything in God's economy.