In "Bullet In the Brain" by Tobias Wolff, in the first part of the story, how is the third-person point of view utilized to depict the characters? How is speech and thought presentation used to shape the reader's understanding of the events and characters in the passage?

"Bullet in the Brain" is, among other things, a story about criticism and critical distance. The use of third person in the story creates a kind of ironic separation between the events of the story, Anders' reaction to them, and the narrator's voice. Take, for instance, the words Anders exchanges with a woman waiting in line when a teller suddenly closes her window:

"Oh, that’s nice,” one of them said. She turned to Anders and add, confident of his accord, “One of those little human touches that keep us coming back for more.”
Anders had conceived his own towering hatred of the teller, but he immediately turned it on the presumptuous crybaby in front of him. “Damned unfair,” he said. “Tragic, really. If they’re not chopping off the wrong leg, or bombing your ancestral village, they’re closing their positions.”
She stood her ground. “I didn’t say it was tragic,” she said. “I just think it’s a pretty lousy way to treat your customers.”
“Unforgivable,” Anders said. “Heaven will take note.”

The narrator understands the attitudes of both Anders and the woman; it is through the narration that we come to see their short dialog as a kind of fight. At the same time, the narration serves as a commentary on Anders' thinking. Anders is a person who clearly hates everything, but the phrase "towering hatred" can only be understood as meant to belittle Anders and paint him as a prig. The fact that the narrator says the woman "stood her ground" implies a kind of approval of this woman's resistance to Anders' rudeness, which suggests that the narrator is functioning as a kind of critic of Anders' own over-developed critical sensitivities. In fact, Anders seems unable to separate reality from text: everything is subject to his critical judgement, even the speech of the hold-up men. It's possible that Anders' sense of distance from the events he witnesses suggests that he confuses himself with the narrator of his story, someone who cannot be affected by the events he narrates.

In Tobias Wolff's short story "Bullet in the Brain," third-person omniscient narration serves a dual purpose. First, by describing the activity in the bank in third person, the author provides a glimpse of many characters without championing the narrative of one. Though the reader gets a better sense of Anders's personality than that of any of the other characters, the setting is immediately relatable to anyone who has had to wait in line for service. The impatience of the customers and disinterest of the tellers are not personal; they are part of a common shared experience.
The second purpose of third-person is to reveal the bank robbers to the reader as they would be revealed to anyone standing in the bank. In contrast, if the story were told in first-person by any character, the reader would automatically be concerned with the fate of just one character. Because of the omnipotent third-person narration, the reader is left wondering what will happen, watching the interaction between the gunman and Anders as anxiously as anyone in the bank. Additionally, because of the omniscient voice, the point of view of the story could shift at any time, adding to the suspense.
The characters' words do not necessarily convey their feelings. For example, Anders is as frustrated with the teller closing her position as the woman in front of him, but he does not give the woman the satisfaction of agreeing with her. Instead, he says, “Tragic, really. If they’re not chopping off the wrong leg, or bombing your ancestral village, they’re closing their positions" (para. 3), minimizing the woman's frustration. This interaction proves to be illustrative of Anders's personality, as he can't keep himself from antagonizing the gunman, even upon threat of harm.