In 1 Corinthians  15:58 Paul writes,

Therefore, my dear brothers, stand firm. Let nothing move you. Always give yourselves fully to the work of the Lord, because you know that your labor in the Lord is not in vain.

Tom Wright (Surprised by Hope, SPCK) places considerable emphasis on this verse, coming as it does after Paul’s great affirmation of physical resurrection.  Although I do not think that Wright offers a novel interpretation of this verse, I do think that he draws out its implications more clearly and helpfully than most:-

For Paul, the bodily resurrection does not leave us saying “so that’s all right; we shall go, at the last, to join Jesus in a non-bodily, Platonic heaven”…Belief in the bodily resurrection includes the belief that what is done in the present in the body, by the power of the Spirit, will be reaffirmed in the eventual future, in ways at which we can presently only guess. (p168f)

Resurrection means that what you do in the present, in working hard for the gospel, is not wasted.  It is not in vain.  It will be completed, will have its fulfilment, in God’s future. (p174)

How does believing in the future resurrection lead to getting on with the work in the present?  Quite straightforwardly.  The point of the resurrection, as Paul has been arguing throughout the letter, is that the present bodily life is not valueless just because it will die.  God will raise it to new life.  What you do with your body in the present matters, because God has a great future in store for it.  And if this applies to ethics, as in 1 Cor 6, it certainly also applies to the various vocations to which God’s people are called.  What you do in the present – by painting, preaching, singing, sewing, praying, teaching, building hospitals, digging wells, campaigning for justice, writing poems, caring for the needy, loving your neighbour as yourself – all these things will last into God’s future.  They are not simply ways of making the present life a little less beastly, a little more bearable, until the day when we leave it behind altogether…They are part of what we may call building for God’s kingdom. (p205)

You are not oiling the wheels of a machine that’s about to fall over a cliff.  You are not restoring a great painting that’s shortly going to be thrown on the fire.  You are not planting roses in a garden that’s about to be dug up for a building site.  You are – strange through it may seem, almost as hard to believe as the resurrection itself  – accomplishing something which will become, in due course, part of God’s new world.  Every act of love, gratitude and kindness; every work of art or music inspired by the love of God and delight in the beauty of his creation; every minute spent teaching a severely handicapped child to read or to walk; every act of care and nurture, of comfort and support, for one’s fellow human beings, and for that matter one’s fellow non-human creatures; and of course every prayer, all Spirit-led teaching, every deed which spreads the gospel, builds up the church, embraces and embodies holiness rather than corruption, and makes the name of Jesus honoured in the world – all of this will find its way, through the resurrecting power of God, into the new creation which God will one day make.  That is the logic of the mission of God. God’s recreation of his wonderful world, which began with the resurrection of Jesus and continues mysteriously as God’s people live in the risen Christ and in the power of his Spirit, means that what we do in Christ and by the Spirit in the present is not wasted. It will last all the way into God’s new world.’ (p219)