When Edith's cousin Amelia comes visiting with her entrepreneur husband, Archie's irritated both by Russell's boasting about his business and Edith's wistfulness in wishing Archie treated her more like Russell does Amelia. Both Archie and Edith soon learn, however, that they themselves are the richer in terms of true happiness and marital contentment.
What makes this episode so wonderful, besides the humorous dialogue, is what is revealed about Archie and Edith that seals our affection for them. As limited and coarse as Archie can be in his thinking, he truly loves and is devoted to Edith, as seen in his statement to Russell about greener pastures ("Edith is green enough for me."). He also believes strongly in fidelity in general, as witnessed when he reprimands Russell for his antics towards the woman at the bar, and reminds him of his "nice wife waiting" back at his place.
Likewise, Edith possesses not even a hint of envy when she hears about Amelia's travels and trips thanks to Russell's successful business. She is genuinely happy for her cousin, and is devastated to learn that it's all superficial, and that there are serious problems in Amelia's marriage.
I believe that this devotion between Archie and Edith along with what is indicative about their individual characters is what makes the audience so fond of them, and I believe the dialogue between Amelia and Edith about what Edith must be doing "right" in bed cements the notion that Archie and Edith have a very active and passionate sex life. It seems a little bizarre to think about, but it was something that the media contributors and critics of All in the Family commented on during the show's actual run.
My favorite part of this episode is the very last scene, in which Edith and Archie sit in mutual silence in their chairs. Archie glances over and sees the look on Edith's face, and silently guesses what she is thinking about now that their company has just left. Worldlessly, he puts his hand over hers in an act of comfort and shared knowledge. It is one of the most touching moments of the series, and is an insight into that hard-boiled sensitivity of Archie's that lends him anotherdimension, not-often-seen.