Irony is when the opposite of an intended action happens. The supposed purpose of Aunt Alexandra's missionary teas is to discuss how they can help people and/or convert them to their religion—the Maycomb Alabama Methodist Episcopal Church South. During the refreshments time, Scout asks the women what they discussed and Mrs. Merriweather is not afraid to declare that pastor J. Grimes Everett has been working with a tribe called the Mrunas who have camped out in a jungle area. She brags that he goes down to help or proselytize to the Mrunas, but no "white person'll go near 'em but that saintly J. Grimes Everett" (230). The irony is that she praises this man for helping these people, but she won't go herself. Not only that, but there are people in her own community who might need help and she will only discuss and berate them rather than go out and actually help them. If she's a missionary attending missionary meetings, shouldn't she act like one and go out herself and visit the people she's discussing?
Mrs. Merriweather continues her hypocritical and ironic claims as she says anyone who is not Christian must be living in "sin and squalor," but again, she hasn't visited them to find out for herself. She only knows what J. Grimes Everett has told her. She even goes so far as to call Tom Robinson's wife, Helen, a "darky" and say that she should live more like a Christian, as in the following paragraph:
"Thing that church ought to do is help her lead a Christian life for those children from here on out. Some of the men out to go out there and tell that preacher to encourage her" (231).
Basically, all Mrs. Merriweather suggests is that other people (men) should go out to the black community and tell Reverend Sykes to encourage Helen to lead a Christian life. Unbeknownst to her, the Robinsons are a churchgoing family. Also, Scout attended Sykes's church and saw for herself that they collected money to help Helen during her time of stress and need. That's the Christian way—not sitting on one's duff criticizing others for what they should be doing. But that's Maycomb—hypocritical and ironic to the very last.
The irony that surrounds the efforts of the women's missionary circle is the fact that these women bemoan the difficult lives of the Mrunas, but are indifferent to the suffering of African-Americans in their own town.
They gossip about Tom Robinson and his wife, unaware that Tom is now dead--shot by prison guards as he tried to escape. They claim to have great respect for J. Grimes Everett's work with the Mruna tribe, but they do not want to offer any of the same Christian charity to the people who are right underneath their own noses.