Theologian David VanDrunen argues for the recovery of the Reformation doctrine of two-kingdoms as a biblical alternative to the contemporary view that characterizes neo-Calvinists (Albert Wolters, Cornelius Plantinga), the New Perspective on Paul (N. T. Wright), and the emergent church (Brian McLaren): the redemptive transformation of culture. Here is the most concise definition I have read on two-kingdoms theology:
This two-kingdoms doctrine strongly affirms that God has made all things, that sin corrupts all aspects of life, that Christians should be active in human culture, that all lawful cultural vocations are honorable, that all people are accountable to God in every activity, and that Christians should seek to live out the implications of their faith in their daily vocations. A Christian, however, does not have to adopt a redemptive vision of culture in order to affirm these important truths. A biblical two-kingdoms doctrine provides another compelling reason to do so. According to this doctrine, God is not redeeming the cultural activities and institutions of this world, but is preserving them through the covenant he made with all living creatures through Noah in Genesis 8:20-9:17. God himself rules this “common kingdom,” and thus it is not, as some writers describe it, the “kingdom of man.” This kingdom is in no sense a realm of moral neutrality or autonomy. God makes its institutions and activities honorable, though only for temporary and provisional purposes. Simultaneously, God is redeeming a people for himself, by virtue of the covenant made with Abraham and brought to glorious fulfillment in the work of the Lord Jesus Christ, who has completed Adam’s original task once and for all. These redeemed people are citizens of the “redemptive kingdom,” whom God is gathering in the church and will welcome into the new heaven and new earth at Christ’s glorious return. Until that day, Christians live as members of both kingdoms, discharging their proper duties in each. They rejoice to be citizens of heaven through membership in the church, but also recognize that for the time being they are living in Babylon, striving for justice and excellence in their cultural labors, out of love for Christ and their neighbor, as sojourners and exiles in a land that is not their lasting home (pp. 14-15).