Second Corinthians 4:7–18 explains that the priceless treasure of knowing God’s glory through faith in Christ is kept in the fragile containers of human beings. In this case, this refers to Paul and his co-workers who preach the gospel. Their suffering is enormous, but God keeps them from being wiped out. They don’t quit because even after they die, they know they will be resurrected, as Christ was. Then they will spend eternity with Him in a glory that will far outweigh and outlast the comparatively lightweight and momentary suffering of this life.
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“2 Corinthians 4:16” Bibleref.com
2 Corinthians 4:16
16 Therefore we do not lose heart. Though outwardly we are wasting away, yet inwardly we are being renewed day by day.