Forrest made a number of similar statements, including this letter, written together with Gideon Pillow, urging his fellow Confederate veterans to participate in Decoration Day (Memorial Day) activities in Memphis in 1875:
"However much we differed with them while public enemies, and were at war, we must admit that they fought gallantly for the preservation of the government which we fought to destroy, which is now ours, was that of our fathers, and must be that of our children. Though our love for that government was for a while supplanted by the exasperation springing out of a sense of violated rights and the conflict of battle, yet our love for free government, justly administered, has not perished, and must grow strong in the hearts of brave men who have learned to appreciate the noble qualities of the true soldier.
"Let us all, then, join their comrades who live, in spreading flowers over the graves of these dead Federal soldiers, before the whole American people, as a peace offering to the nation, as a testimonial of our respect for their devotion to duty, and as a tribute from patriots, as we have ever been, to the great Republic, and in honor of the flag against which we fought, and under which they fell, nobly maintaining the honor of that flag. It is our duty to honor the government for which they died, and if called upon, to fight for the flag we could not conquer."
Now, having said that, I think it's really skating out onto thin ice, historigraphically, to necessarily attribute this to a religious conversion or redemption. Those are matters of the soul or conscience that we simply cannot know with any certainty. (As Sagebrush suggests, there are plenty of people today who make a big show of their pious Christianity, who aren't especially nice people.) A cynical person would also point out that, by this time, most of Forrest's postwar political goals of pushing back against Reconstruction and re-establishing something akin the to the social, political and racial
status quo antebellum had been accomplished, so Forrest could well afford to make a public show of being magnanimous to both African Americans (e.g., his Pole-Bearers' speech) and to his former enemies.
Forrest is a fascinating character, but I'm not sure anyone can really fully understand him, and chalking it all up to a near-deathbed conversion and being filled with the Holy Spirit just strikes me as being a little too easy an explanation. YMMV.
Finally, the point about Forrest's public statements (whatever their origin) and the over-the-top rhetoric of some modern-day "heritage" folks is well taken.
I've encountered very few memoirs or accounts by real Confederate veterans that are as full of anger and vitriol as expressed by some Confederate heritage folks today. The difference, I think, is that real Confederates didn't need to prove their bonafides, and today's make-believe Confederates never can.