Scripture
2 Corinthians 4:16-18 NIV
Therefore we do not lose heart. Though outwardly we are wasting away, yet inwardly we are being renewed day by day. For our light and momentary troubles are achieving for us an eternal glory that far outweighs them all. So we fix our eyes not on what is seen, but on what is unseen. For what is seen is temporary, but what is unseen is eternal.
Consider
The “outward” and “inward” selves that Paul describes are not our body and our spirit, as one might suppose. Rather, Paul is contrasting the two ages in which every Christian lives.