First of all, let us notice how Christ is called "the last Adam." In verse 45, "The first man Adam" and then (in the next sentence) "the last Adam."
"The first Adam" brings to mind the concept of the first of a new breed, created in the image of God. That was something "new"—to have a creature in the image of God.
After being called "the last Adam," we find Him called "the second Man" in verse 47. Then, we find Him called "the heavenly Man." He is called "the second Man" (or "the second Adam") and "the heavenly Man" in order to draw our thinking away from "the first Adam"—who was, you see, the first of a new breed—to "the second Adam" (or, "the second Man") or "the heavenly Man"—who is also the first of a new breed. "A new creation," as it were.
So the new breed are those who are after Christ and not after Adam. The new breed (or, the new creation) is of a heavenly, spiritual orientation. And it is the image of "the second Man"—"the second Adam"—"the heavenly Man," which we are being transformed into. That is what we are going to bear.
In our life, there is a process of development going on—proceeding from that which is natural (Adam, of the dust) to that which is spiritual (Christ, of heaven). First we are from Adam, and his origin was from the earth. And, though Jesus was born on the earth, His origin was from heaven. So Adam is first the pattern, as to nature, of all that follow him. This is the important thing right now, for you and me. Adam was the pattern of all of mankind—all who followed him—as to nature; and those who are "of Christ" are of the same nature as He. Peter says that we are of "the divine nature." That is, a heavenly nature—a spiritual nature.
Here we have that dichotomy. Christians are not only earthy—they are also heavenly, because of their relationship with God through Jesus Christ! Putting these scriptures together then, thus the image of Christ is being created in us through this transformation.
