“God put this power to work in Christ when He raised Him from the dead and seated Him at His right hand in the heavenly places, far above all rule and authority and power and dominion, and above every name that is named, not only in this age but also in the age to come” (Eph. 1:20-21).
What the Apostle Paul says here applies to Christ in His human nature, not in His divine nature. As regards His divinity, Christ did not need to be exalted, nor raised from the dead, nor anything of the sort. His divinity remains unchanged and unchangeable for all times. When the Son assumes human nature, He does not empty Himself of His divine nature or cease to be God in order to become a human. Rather, Christ dies, is exalted, and all the rest only insofar as His human nature is concerned.
What might be the significance of all this? To my mind, what is amazing is how much God loves human beings. Ps. 8 extols God who, in spite of His greatness and the majesty of His creation, nevertheless cares for human beings and has made them “a little lower than God” (v. 5) and has put “all things under their feet” (v. 6). Of course, all of this is true in a limited sense in the case of all human beings. This is what the psalmist had to work with; he only knew of the majesty and dominion of human beings insofar as this was visible at his point in history. But his words take on even greater significance and literal truth when they are considered in comparison to Christ, who is a human being ascended into heaven and made lord over the entire cosmos. Jesus Christ possesses a name that is higher than every name, and He possesses this as a human being. This is how much God loves human beings — He lifts them up higher than they can lift themselves, upon the rock that is too high for them (Ps. 61:2).
One way of understanding all this is as follows. God had a certain purpose in mind for human beings when He created them. He had certain grand plans for them. Of course, because of their sin, they failed to live up to this calling and instead found themselves brought very low. But in the Incarnation and the entire work of Christ, human nature is restored, brought up from its lowly place and, in the person of Christ, is lifted up higher than would have been possible for it by itself. Christ fulfills the calling that God had for human beings and received in Himself the reward which God intended for us all along. In Christ, the human being has reached perfection and has accomplishes its purpose. Christ is the one true human being.
This doctrine is referred to as the “vicarious humanity of Christ.” In Christ, we see human nature in its true form, in complete harmony with the design of God, as it should be. Christ is the true and perfect human being. And if we are united with Christ, if we are in communion with Him, then He shares His glory with us and makes us to be true human beings, as well. We begin to participate in this dominion and authority of Christ — not making use of it for our own purposes, as if Christ were a genie at our disposal, but caring for the earth and for others in keeping with His example, knowing that we are under His care and that we can appeal to Him for anything.