In what ways does Douglass emphasize the corrupting nature of slavery to American society? More specifically how does this corrupting influence shape what he argues are American institutions such as womanhood? Christianity?

Douglass emphasizes the ways in which slavery corrupts slaveowners. His audience is white northerners whom he hopes to sway against slavery and towards abolitionism by emphasizing the evils of slavery and its corrupting effects on whites, including Christians.
The person who embodies these corrupting effects is his slave mistress, Sophia Auld, in Baltimore. As she is a northerner, she is at first not aware of the southern ban against teaching slaves to read, and she begins to instruct Douglass, then a young boy, how to read. Her husband scolds her and tells her that learning will forever spoil a slave, and Sophia Auld halts her instruction of the young Douglass. Douglass portrays how Sophia Auld, once a kind and Christian woman, is turned into a vengeful and evil soul by slavery. In the character of Sophia Auld, he dramatizes the corruption that slavery brings to whites.
In addition, Douglass shows that slavery is degrading to people's practice of Christianity. He writes about how his master, once turned religious, becomes even more hypocritical because the master believes that the tenets of Christianity (as practiced in the South) permit slavery. Douglass writes, "For of all slaveholders with whom I have ever met, religious slaveholders are the worst. I have ever found them the meanest and basest, the most cruel and cowardly, of all others." Though he was criticized for his claims, Douglass maintained that the slaveholding Christianity of the South is not true Christianity but is entirely antithetical to what Christianity means. In his narrative, he describes the corrupting influence of slavery on American institutions such as womanhood and religion.