This week's White Horse Inn podcast touches on the vocation of Christians. Fundamental to a solid theology of vocation is a proper understanding of the "two kingdoms" i.e. the kingdom of God and the kingdom of this world. Before the fall, in the garden, the kingdom of man was the kingdom of God. Man's realm belonged to God and, if I may say anachronistically, man belonged to a Christian culture.
Ever since the fall, man was driven from God's presence. No longer was the dwelling of God with man. Sure, mankind could still work, have children and build cities, but these societies did not have God walking among them. To cut a long story short, it's only in the NT with the coming of Christ that we see the return of the kingdom of God. Yet even still, his kingdom was and is not of this world. He inaugurated a new creation in his death, burial and resurrection and we await the final renewing of the heavens and the earth.
So at the moment, Christians are kind of stuck in a tension. We live in the world but we are not of the world. We are aliens and strangers whose citizenship is in heaven with Christ. This present evil age is passing away. Therefore, it is utter folly for the church to attempt to "transform the culture", a culture which is being prepared for burning.
The church's job is to announce God's kingdom through the preaching of the risen Christ and the administration of the sacraments. It seems weak and foolish compared to the whole "fighting injustice for Jesus" emerging ethos, yet it is God's plan.
This is fundamental if we are to grasp the purpose of our vocation. If the church is about word and sacrament and not about transforming culture, then what of the laity? What are we to do? It seems that our whole purpose is to live in this fallen world quietly and humbly going about our jobs. The apostle even wrote to make it your ambition to lead a quiet life and work with your hands so that you might win the respect of outsiders. The purpose of the church is to feed us with Christ, so that we might have the resources to be salt and light in our vocation. God is more pleased with a street-sweeper who sweeps for the glory of God than one who locks himself away praying 24/7 in a monastry.
There is an interesting point from 1 Corinthians 15:58 where Paul tells us that our "labour in the Lord is not in vain." There seems to be an echo from Ecclesiastes here, where we are told that the whole of life (work, play, laughter, etc) is "vanity". Yet for those of us in Christ, all these things (work, play, laughter, etc) are not in vain. We can do the most mundane tasks knowing that, done in Christ, they have purpose in God's eyes.
Your job isn't a waste of time. If it's done in Christ it's valuable to our heavenly Father.