When Malamud introduces the plot to the reader in "The Magic Barrel," the first thing he does is set the mood. Then he describes how Salzman and Leo Finkle come to know each other. Leo shares his purpose with Salzman, which advances the rising action, while the conflicts are also presented.
The mood has elements of mysticism. It begins with a line very similar to a fairytale's "once upon a time:"
Not long ago there lived...
Salzman, the owner of the "magic barrel" (which the Leo never does see) "appeared one night out of the dark fourth-floor hallway..." Like a magician, Salzman might be thought to be carrying his "tricks" in his black bag (similar to a magical black hat), which he grasps to himself tightly. While Leo is nervous about engaging a matchmaker, Salzman inspires some confidence in him; the mood has a hint of magic and possibilities when Salzman first shows up.
The narrative describes Leo and his educational endeavors; his desire to find a wife so that he can more easily "win himself a congregation;" and, his uneasiness in taking this step: nerve-wracking on its own, this is an old-fashioned, time-honored tradition used to find a wife—something Leo's parents and/or grandparents would have done. Leo seems a traditional young man.
Salzman is rather a shabby figure that appears to have been doing this work for a long time, but not necessarily with great success. His clothes are tight and worn—as is his bag—and he wears an old hat, but he has a "dignified build." His eyes are kind and his manner is relaxed and easy-going. The cards he holds are almost as worn as the man who holds them.
As Leo explains why he has engaged the matchmaker, the reader also learns of his intent. Leo presents his wishes in a business-like manner, and Salzman...
...eagerly unstrapped his portfolio and removed a loose rubber band from a thin packet of much-handled cards.
As this segment begins, the worn cards (studied and rejected countless times) also creates a sense of about. But while Leo is hesitant about this professional arrangement, Salzman is deeply enthusiastic. (Their relationship will continue in this manner until Leo sees Stella's picture: then Leo will be enthusiastic and Salzman filled with trepidation.)
In this way, the author presents the mood, describes the characters—defining their early relationship—and presents the details that have brought these characters together.