In Hart and Muether's history of American Presbyterianism, Seeking a Better Country, they describe a doctrine of the "spirituality of the church," which emphasizes the spiritual, not social, task of the church:
The church was not commissioned to make the world a better place in which to live. It had no business telling the government how to rule the body politic. It was not to feed the hungry, or provide houses for the homeless, or protest social injustice. These political and social temptations only distracted the church from its spiritual calling. (223)
This view was "championed by James H. Thornwell," one of the most prominent 19th-century Southern Presbyterians. But in what seems to me a contradiction, Thornwell is cited by others as an advocate of theonomy, which Wikipedia defines:
the idea that God's Law-Word, including the judicial laws of the Old Testament, should be observed by modern societies.
For example, theonomist Greg Bahnsen writes:
Even into the late nineteenth century respected Reformed theologians were contending that the state should conform its laws to those found in the law of God. The southern presbyterian, James H. Thornwell, stated in 1861: "We long to see, what the world has never yet beheld, a truly Christian Republic." (source)
Put simply, my question is: how are these two views are reconciled in the thought of Thornwell and other theologians who hold these two views? How did he/they see the spirituality of the church and theonomy as non-contradictory?