2 Corinthians 4:16–18: Suffering Is Not What It Seems
Paul does not deny that the outward person is decaying. He says decay is not the whole truth, because God renews the inward person day by day and the unseen things are the eternal ones.
Hebrews 11:1–6: What Faith Actually Is
Hebrews 11:1–6 describes faith as settled confidence in what God has promised and inward proof of realities not yet seen, the same faith that marked God's people from Abel onward. Verse 6 presses the claim: coming to God means believing he exists and that he rewards those who seek him.
Why your circumstances dont define your spiritual growth
Paul does not deny that faithful servants of Christ wear down and suffer. He refuses to let those visible things measure the inward person, because God is renewing what cannot be seen and the glory ahead outweighs it all.