Adam (v.45) — had life, but couldn’t give life to others
spiritual is not first (v.46) — Humans begin with only the natural life and then receive the spiritual
of the earth (v.47) — Adam was formed of the dust of the ground
earthy (v.47) = lit. “dusty, muddy” — referring to origin and characteristics
the Lord (v.47) — not in the best manuscripts
From Adam all members of the human race spring. From Christ all members of the new world of Christian men spring. After creating Adam, the creative process ceased. From Adam the race springs by natural law. After Christ the incarnation ceased. From Him the new race springs by spiritual law. — Laurin, page 296.
heavenly (v.48) — referring to origin (in the sense of where He was from) and characteristics
those who are made of dust (v.48) — those descended from Adam — humanity — those who take on his characteristics
those who are heavenly (v.48) — those who receive spiritual life from Christ are “seated together with Christ in heavenly places” and take on heavenly characteristics
Just as surely as we now bear the image of the muddy old Adam so surely shall we bear the image of the heavenly Adam. Alas, in this sinful state here below we show His image all too little! God predestinated us to be conformed to the image of His Son (Romans 8:29) and His predetermination shall not fail but will be fully realized some day. Old Adam’s impress is still in the way. The world is in the way and our sinful old self is still marring our likeness to the Son. With our humiliated bodies we still bear the stamp of old Adam, the mud man, but spiritually we are already united to the second Man from heaven, and no power in heaven, earth or hell can break the bonds that binds us to Him. By looking unto Him we undergo even now a spiritual transformation (2 Corinthians 3:18); but at the resurrection His mighty energy shall make even our bodies like unto the body of His glory (Philippians 3:21). — Bultema, page 146
image (v.49) = representation and manifestation (Romans 8:29; 1 John 3:2)
The two questions raised in verse 35 have been completely answered. As to the first, it has been show that, instead of resurrection being impossible on account of the condition of the body after death, that very condition is essentially preliminary to resurrection, for it involves the principle of a new life. And as to the second, the resurrection body is to be in the likeness of that of the risen Lord. — Vine, page 115.