Chapter 24 is all about the meeting of the Ladies Missionary Circle to discuss the course that Mrs. Merriweather is giving on the Mruna people of Africa. They discuss the missionary J. Grimes Everett's work and the poor people of the African jungle and their terrible conditions, according to Everett:
"The poverty...the darkness...the immorality" (Ch.24).
Mrs. Merriweather promised J. Grimes Everett that when she returned back home from her trip to his camp that she would teach a course on the Mrunas, and that is what the meeting in Ch. 24 is supposed to focus on.
Of course it goes in another direction entirely when the ladies of Maycomb begin talking about their hired help, all of whom are African-Americans. Their sympathy for the Africans in the jungle is not the same sentiment they have for their African-American servants, who they find to be ungrateful. Lee's point in this chapter, and of this meeting, is to show the hypocrisy of some of the good Christians of Maycomb.