I believe the origin of this idea comes from certain writers such as Francis Schaeffer and CS Lewis. Lewis, as I recall, made a comment to the effect that the clergy wasn't supposed to do everything, but, that "....the application of Christian principles to, say, education or trade-unionism, should come from Christian schoolmasters and Christian trade-unionists..." and that "good philosophy must exist, if for no other reason than that bad philosophy needs to be answered."
Or, to put Lewis' point another way, the culture will be reformed when many individual Christians apply their faith and convictions to their particular profession or sphere of influence -- whether you're a philospher, a pre-school teacher, or a politician. As I see it, this is simple discipleship, simple obedience. Hence, "reclaiming the culture" is nothing more, less, or else than the earthly side effect of Christians obeying God. Note well that I said "side effect", not primary goal. Calls to "reclaim the culture" are therefore (a) wrong if they prioritize reclaiming Earth over claiming Heaven (Seek ye first..), but (b) right if they shake socially complacent Christians into awakening to this particular, oft-neglected aspect of discipleship.
I'll just check back every 5 years or so for a progress report on the "cultural commission". I predict it will fail demonstrably
Alas, I doubt it will be seriously tried, because the vast majority of American "Christians" don't actually have a biblical worldview and hence don't make biblical decisions about any area of life -- certainly not career or cultural engagement.
This is magnificent and we fully agree right here, at least. (emphasis mine, of course)
And anyone who alludes to Frances Scheaffer and C.S.Lewis I count a companion, whether he wants me to or not! :-)
Warmest regards.