This Modern Reformation article by Dr. Gene Veith gives a great overview on the doctrine of vocation. Veith’s writings, particularly Loving God With All Your Mind and God at Work were very influential for me as I wrote the academic chapters of Thriving at College.
An excerpt:
The doctrine of vocation is the theology of the Christian life. It solves the much-vexed problems of the relationship between faith and works, Christ and culture, how Christians are to live in the world. Less theoretically, vocation is the key to strong marriages and successful parenting. It contains the Christian perspective on politics and government. It shows the value, as well as the limits, of the secular world. And it shows Christians the meaning of their lives.
The Swedish theologian Einar Billing, in his book Our Calling, noted how our tendency is to look for our religion in the realm of the extraordinary, rather than in the ordinary. (1) In vocation, however, God is hidden even in the mundane activities of our everyday lives. And this is his glory.