The southern churches, for all their vaunted orthodoxy, could not wholly resist the rising tide of theological liberalism, as capitalism inexorably transformed the world into one grand marketplace of ideas as well as commodities. No society could insulate itself from marketplace sentiments and ideas, which themselves metamorphosed into commodities. Supposedly, heresies, cults, and isms flourished only in the free states, but they were making troublesome inroads into the slave states. Vigilance emerged as the South's order of the day.

Long-standing theological and ecclesiastical differences within the national Presbyterian Church flared into acrimony in the 1830s, and the split in 1837 between the orthodox Calvinist Old School and the more variegated New School exposed the strength but also the greater weakness of theological liberalism in the South. Beneath ecclesiastical and political issues lay theological ones: faithfulness to the Orthodox Westminster Confession and to the formulaic five points of Calvinism or “TULIP” (total depravity, unconditional election, limited atonement, irresistible grace, and perseverance of the saints). The New School arose in the Northeast primarily among men who professed to defend Calvinism against the Unitarians but who made more and more concessions to advocates of free will (Arminians). They repudiated predestination or interpreted it so flexibly as to make Arminians gloat over their surrender.