The first man [i.e., Adam] came from the dust of the ground [See Gen. 2:7]; the second man [i.e., Christ] came from heaven.

Just as earthly people are like the man who came from dust; so heavenly people are like the man who came from heaven.

And just as we [now] appear [in both a physical and spiritual body] like the man who came from dust [i.e., Adam]; we will also [someday] appear [in both a physical(?) and spiritual body] like the man who came from heaven [i.e., Christ].