What divides American Christians?

At least theologically, there are two effective divisions between American Christians, One is between those for whom the gospel is itself the norm of all truth and the person of Christ therefore the founding metaphysical fact, and those for whom some other agenda or “theory” is the overriding norm. The other is between those who use “justification by faith” — or in the especially aggravated case of Lutherans, the “law and gospel” distinction — to fund their antinomianism, and those appalled by this. The language in which I have described the alternatives will doubtless betray on which side of each division I find myself.

-Robert Jenson, Christian Century (May 2, 2007)