Next to Robert Lewis Dabney (1820-1898), James Henley Thornwell (1812-1862) was a very influential Southern Presbyterian theologian. According to Dr. Curt Daniel, R.L. Dabney was the Southern counterpart to Charles Hodge of the North. So, it seems that Dabney was the more influential Southern theologian.
The following is an excerpt taken from a link partially entitled “Southern Presbyterian Heretics”:
Here’s a Thornwell quote:
“There is a difference between them [election and reprobation], however; election finds the objects of mercy unfit for eternal life, and puts forth a positive agency in preparing them for glory; reprobation finds the objects of wrath already fitted for destruction, and only withholds that influence which alone can transform them. … reprobation is strictly an act of sovereignty in which God refuses to save, and leaves the sinner to the free course of the law. … Our Standards afford no sort of shelter to the Hopkinsian error that the decree of reprobation consists in God’s determining to fit a certain number of mankind for eternal damnation, and that the Divine agency is as positively employed in man’s bad volitions and actions as in their good.” (from Collected Writings II) http://www.outsidethecamp.org/efl41.htm
Here Thornwell shows that he believes in conditional reprobation, contrary to the Scriptures which say that Esau was reprobated BEFORE he had done anything evil (i.e., unconditional reprobation). Thornwell is also saying that God’s agency is NOT positively employed in man’s bad volitions! So, God just “lets them go their own way” without any intervention in their lives. This is a form of semi-deism/dualism, and it is totally contrary to the Scripture (see Deut. 2:30; 2 Sam. 17:14; 1 Kings 22:20-23; 2 Chr. 18:22; 2 Chr. 25:17-23; Ps. 105:25; Prov. 16:4; Prov. 21:1; Isa. 6:9-10; Isa. 19:14; Isa. 45:7; Acts 4:27-28).