Nettie tells of their preparations before their trip for Africa: Corrine made traveling outfits, and Nettie, in church, realized that "Ethiopia," in the Bible, refers to all of Africa, and that Jesus' hair, described as being like "lamb's wool," implies that Jesus was not white-skinned, as many white people wish to believe.
As Nettie becomes more knowledgeable about the world and more comfortable in it, she starts to see that the ideas forced on her by white culture aren't necessarily truth. In seeing Jesus as being non-white she begins to see worth in being non-white; she begins to see worth in herself.
Nettie reports on their train-trip from Georgia to New York City, from which they set sail. Nettie sees Harlem, the largest black community she has ever experienced, and Samuel, Corrine, and Adam and Olivia collect money for their missionary activities from preachers and members of church congregations throughout New York.
Harlem, at this time, was a Mecca of African American culture—music, religion, poetry, and art. Nettie is exposed to this culture and hopes to relate it to Celie, as a means of showing that African Americans, despite their social subjugation in the South, are producing great works up North, and are participating in New York City's economic and social life. In other words, that the African Americans situation in the South is imposed upon them, not something they deserve. In relating this information, Nettie is relating her realizations about the potential of black people, which is so stunted by racism in the South.
Nettie tells of her brief, two-week training in New York in the Olinka dialect—the Olinka are the African people they will be serving overseas. Nettie is confused by the white members of the Missionary Society of New York, who make it seem that their white missionary workers are better suited to tending to their African congregants than are black people like Corrine, Samuel, and Nettie.
Nonetheless, there is still racism in the North, too. And even those whites who want to do good, who want to help the people of Africa, instinctively think of themselves as superior to black Americans wanting to do the same work.