What have Scout and Jem learned about Calpurnia? About her people? About the town they are growing up in?

Chapter 12 offers the one real window into the life and culture of Maycomb's black community. The scarcity of views into the "Quarters," the black residential part of town, most likely reflects accurately upon what it would be like to grow up as a white girl in the Deep South in the 1930s. Scout lives almost exclusively in a middle-class white world, and as the book tends to stay centered around her own experience, it almost never moves into other racial circles. The narrowness of her own experience, seen through the book, demonstrates the rigidity of Maycomb's segregated society.

The First Purchase church is noticeably shabbier and simpler than Scout's church, reflecting the material poverty of its congregation. However, though materially poor, the congregation displays a richness in human and spiritual dignity. Though exposed to decades of white racist hatred and discrimination, the entire congregation (except Lula) gives the Finch children a warm welcome. For the most part, the black community seems unified in a sense of solidarity that their poverty and shared hardships help to solidify. The Reverend singles out individuals in front of the group in his sermon because within a community of discriminated people, the actions of individuals have a more profound effect upon the image of the entire group. Thus, it becomes every individual's responsibility to act with the group's common goals in mind. Likewise, in making a collection for Helen Robinson, everyone in the community must sacrifice a little more than they are comfortable with in order to help out those in need. In a more affluent social group, the very wealthy can act as philanthropists, doling out large sums to support the very poor without significant sacrifice to their own large fortunes. In the black community, the needs of the poorest members are felt by everyone else in the group.

Despite the differences between the black and white congregations, Scout notes that most aspects of the service are very similar, including the nature of the sermon itself. This demonstrates that the two groups, though so socially segregated, share much in common where the issue of faith is concerned. Like the courtroom (house of the state), later in the book, the church (house of God) is a space in which all people can be treated on equal terms.

Calpurnia's ability to speak both the English of the white community and of the black community shows one aspect of her role as a mediator between the otherwise far-removed worlds of black and white. She is often called upon as a go-between between the two communities, as in the case of the death of Tom Robinson in chapter 24. She manages to bridge both worlds without becoming a foreigner to both, as in the case of the "mixed" children seen around the courthouse in Chapter 16. However, the discussion of English dialects also dates Lee's book considerably, as white grammar is referred to as "proper" English, whereas black grammar comes across as being a more ignorant way of speaking. More recent linguistic research has demonstrated that the dialects of African-American English follow the same logical, systematic rules as all languages and are correct and perfectly contained unto themselves. Calpurnia explains that members of the black community prefer to speak their own form of English, which shows that their dialect helps to identify them as a group, an idea which has contemporary reverberations with respect to the issue of introducing Ebonics in American public schools.

Lula's defensive attitude toward allowing the Finch children into the church demonstrates that although the black community is by and large welcoming, there are always people, black or white, who are less generous or unfair, which relates to Atticus's courtroom speech where he explains that there are honest and dishonest people everywhere, regardless of race. Creating one somewhat hostile black character in Lula, saves the black populace from becoming an unrealistic stereotype for unambiguous "good" in the book. The experience of being temporarily restricted from the space of the church also forces the Finch children to momentarily experience the same kind of racial discrimination that is a terrible daily reality for the black community. Lula's actions suggest that in retaliation against the cruelty of white domination, she wants the black community to, like whites, have their own spaces and lead mutually exclusive lives. The others, however, seem more interested in working toward a peaceful integration between blacks and whites despite historical atrocities and animosity.