For if the dead are not raised, not even Christ has been raised. And if Christ has not been raised, your faith is futile and you are still in your sins. Then those also who have fallen asleep in Christ have perished. If in Christ we have hope in this life only, we are of all people most to be pitied.
But in fact Christ has been raised from the dead, the firstfruits of those who have fallen asleep. – 1 Corinthians 15:16-20
For as by a man came death, by a man has come also the resurrection of the dead. For as in Adam all die, so also in Christ shall all be made alive. But each in his own order: Christ the firstfruits, then at his coming those who belong to Christ. Then comes the end, when he delivers the kingdom to God the Father after destroying every rule and every authority and power. For he must reign until he has put all his enemies under his feet. The last enemy to be destroyed is death. – 1 Corinthians 15:21-26 (ESV)
Everything sad is going to come untrue and it will somehow be greater for having once been broken and lost. Embracing the Christian doctrines of the incarnation and Cross brings profound consolation in the face of suffering. The doctrine of the resurrection can instill us with a powerful hope. It promises that we will get the life we most longed for, but it will be an infinitely more glorious world than if there had never been the need for bravery, endurance, sacrifice, or salvation. — Tim Keller
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)
Everyone is Niggle. Everyone imagines accomplishing things and everyone finds him or herself largely incapable of producing them. Everyone wants to be successful rather than forgotten, and everyone wants to make a difference in this life. But that is beyond the control of any of us. If this life is all there is, then everything will eventually burn up in the death of the sun and no one will even be around to remember anything that has happened. Everyone will be forgotten, nothing we do will make any difference, and all good endeavors, even the best, will come to naught. Unless there is a God. If the God of the Bible exists, and there is a True Reality beneath and behind this one, and this life is not the only life, then every good endeavor, even the simplest ones, pursued in response to God’s calling, can matter forever. You are likely to get discouraged because throughout your life you probably will not get more than a leaf or a branch done. But there really is a New Jerusalem, a heavenly city, which will come down to earth like a bride dressed for her husband. – Tim Keller