Therefore, my beloved brothers, be steadfast, immovable, always abounding in the work of the Lord, knowing that in the Lord your labor is not in vain. ( 1 Corinthians 15:58 ESV )
“Therefore”—Paul has spent chapter 15 showing that believers possess eternal life and will one day be given glorified bodies, and so in this last verse he states that because we know this is our destiny, it should change our attitudes and actions. He knows how easy it is for us to accept compromise in our morals, to be wavering in the truth, to be lackadaisical in our works. But if we are always keeping in mind our eternal destiny, our normal pattern should change to being “steadfast, immovable, always abounding in the work of the Lord,” even though it is hard, because we know our labor “will not be in vain” that there will eternal results and rewards. Knowing we have eternal life should make an eternal difference, both in our lives and in the lives of others.