“One of the difficulties [in 1 Corinthians 15:44] is that the expression “a spiritual body” has led many to think that the resurrection body will be a nonphysical one—spiritual is then thought to be in contrast with physical.
That this is not so can be easily shown. The resurrection body of the believer, we have seen, will be like the resurrection body of Christ (cf. 1 Cor. 15:48, 49). But Christ’s resurrection body was certainly a physical one; he could be touched (John 20:17, 27) and he could eat food (Luke 24:38-43). Further, the spiritual…does not describe that which is nonmaterial or nonphysical.
Note how Paul uses the same contrast in the same epistle, chapter 2:14-15: “Now the natural…man receiveth not the things of the Spirit of God: for they are foolishness unto him; and he cannot know them, because they are spiritually judged. But he that is spiritual…judgeth all things, and he himself is judged of no man” (ASV).
Here the same two Greek words…are used
as in 15:44. But spiritual…here does not mean nonphysical. Rather, it means someone who is guided by the Holy Spirit, at least in principle, in distinction from someone who is guided only by his natural impulses. In similar fashion, the natural body described in 15:44 is one which is part of this present, sin-cursed existence; but the spiritual body of the resurrection is one which will be totally, not just partially, dominated and directed by the Holy Spirit.
Our future existence…will be an existence completely and totally ruled by the Holy Spirit, so that we shall be forever done with sin. Therefore the body of the resurrection is called a spiritual body, Geerhardus Vos is correct when he insists that we ought to capitalize the word spiritual in this verse, so as to make clear that the verse describes the state in which the Holy Spirit rules the body.”
-Anthony Hoekema, The Bible and the Future, 249-250.