It’s very easy to dislocate daily renewal (personal growth, progressive sanctification) from the much broader picture of God’s redemptive plan for your life and from future personal bodily resurrection. Our hope of resurrection does not negate the value of our daily progress; daily progress does not diminish the incredible transformation that must happen in the resurrection. In that light Murray Harris makes an important point in his comments on 2 Corinthians 4:16, and the place of this text within the broader flow of Paul’s book. Harris writes:

For Paul, the spiritual body was not simply the state of the renewed “inner self” at the time of the believer’s death, but it seems a priori likely that he saw a relationship between the two, that he regarded resurrection not as a creatio ex nihilo, a sudden divine operation unrelated to the past, but as the fulfillment of a spiritual process begun at regeneration. The daily renewal of the “inward person” (2 Cor 4:16) contributed toward the progressive transformation of the believer into the image of Christ (3:18) in a process that would be accelerated and completed by resurrection. Paul does not explicitly say that his ἔσω ἄνθρωπος [“inner self”] is the embryo of the spiritual body or bears its undeveloped image, but the natural transition of his thought from 4:16 to 5:1–4 shows that this sentiment would have been congenial to him. As a result of the final convulsion of resurrection, the butterfly of the spiritual body will emerge from the chrysalis of the renewed “inner person.”

[Source: Murray Harris, The Second Epistle to the Corinthians, 360.]