The surviving letters of Thomas D. Witherspoon, most addressed to members of the Rascoe family, include a small number of insightful Confederate letters. There are, unfortunately, large gaps in the correspondence, most notably between July, 1862, and 1870, interrupted by only one letter from Witherspoon, January 7, 1864, and this lacuna conceals the entirety of Witherspoon's imprisonment, the end of the war, his departure from the service, and his adjustment to civilian life and Reconstruction. The surviving correspondence, however, forms an interesting and surprisingly fleshed-out portrayal of one man's service as a Confederate chaplain during the earliest stages of the war.
As an educated, clear-thinking, and utterly committed man, Witherspoon is an ideal correspondent. His letters are filled with emotion, driven by a sense of purpose in his military service, and ordered by a strongly held code of morality. His religious leanings and training make him particularly sensitive to the moral state of the Confederate army, and somewhat prone to viewing the conflict as an almost Manichean struggle between southern Good and northern Evil. The scattered letters written during the late spring and summer, 1864, include additional comments on organized "Christian" relief during the war, including a particularly interesting comment from Witherspoon that the (northern) Christian Commission does more to crush the rebellion than the entire Army of the Potomac through their intrigues and trickery in getting sick and wounded men to take the oath of allegiance (1864 January 7).
After the war, Rev. Witherspoon settled in Memphis, Tennessee, and published at least two works: Children of the Covenant (Richmond, Presbyterian Committee of Publication, 1873) and The Appeal of the South to its Educated Men (Memphis: The Association, 1867). He also contributed an essay, "The doctrinal contents of the confession" to the Presbyterian Church's Memorial volume of the Westminster assembly, 1647-1897 (Richmond: Presbyterian Committee of Publication, 1897).
Witherspoon was also author of "Prison Life at Fort McHenry." Southern Historical Society Papers 8 (1880): pp. 77-82, 111-119, 163-68.