Schizophrenia
Nat Turner suffers from delusions of grandeur. Whether his claims are true or not, he defends his aspirations toward greatness by saying he was taught as a child to believe that he was destined to become a prophet. Growing up, he fed this longing for leadership by becoming reputable among his fellows slaves. The way he talks about himself, it's obvious that Turner believes he has some sort of divine anointment to lead his people in a revolt, like Moses in the Old Testament. Unfortunately delusions of grandeur are symptomatic of schizophrenia. Add to that visions of spiritual beings revealing secrets to him, and it becomes pretty clear that Turner is suffering from disassociation. He does not confess to hearing voices, but this vision of the Holy Spirit may qualify if it's not an isolated incident. When he begins the revolt, Turner immediately becomes unpredictable in his violence. He turns on the white owners and brutally murders them, including their wives and children, none of which his followers had anticipated. His violent mood shifts and inflated sense of internal destiny point strongly to his unsettled mind most likely due to schizophrenia.
Revolution
Obviously Turner's rebellion is a story of revolution, but its roots run deeper than expected. Turner is raised believing in the Judeo-Christian traditions, his family being religious like many other slaves during that time. Growing up hearing about the Hebrew slave uprising in Egypt, Turner has adapted the myth for his own purposes. Moses was a Hebrew who was raised in the house of Pharoah as his daughter's son. When he was a man, he had a vision from God which told him to lead the Hebrew slaves -- his people -- out of Egypt into a Promised Land which the Lord said he had prepared for them. Turner hears this story and quickly places himself in Moses' shoes, having grown up believing he was a prophet destined for greatness. He readily steps into a role which he has crafted for himself in order to make his masters pay for their cruelty. In a way, then, there is nothing novel about the Turner's uprising at all. It's just like all other slave rebellions, which always escalate in violence beyond necessity or comprehension. The slaves are tired of their horrific treatment, choose a leader, and execute their vengeance by any means necessary, but in this particular case they are unsuccessful because the movement is too small and limited in geographical space to succeed. Eventually they have no where left to go to escape the militia.
Divine Intervention
The other prominent theme of this text is divine intervention. In his interview with the lawyer, Turner speaks from a place of assurance. He neither believes that he's done anything wrong nor that he's failed. Somehow he's still clinging to the belief that he is the one who will save his people. In his arrogance and eagerness to be a hero, Turner misses the real claim of Moses. Moses was a reluctant messenger who begged God to send someone else. He convinces Pharaoh to free the slaves only by demonstrating the power of God on whose behalf he is speaking. He's giving glory to God throughout the process, merely a servant. For his part, Turner knows the story of Moses well enough to have been able to understand Moses' real function. Turner, however, is compelled by his delusions to seek all the glory for himself. Although he claims to have received a vision from the Holy Spirit to lead this rebellion, he does not credit God with the rest of the battle. Instead he starts brutally murdering everyone, even those who do not stand between him and his freedom. It's no longer about helping free his fellow man; it's about ego. This is why Turner fails. Unlike Moses who acts on behalf of the deity through no selfish interest, Turner makes himself the central figure of his mission and consequently loses sight of his true purpose of freeing the slaves.
