Throughout the play, Estragon often appears more confused and less satisfied than Vladimir. He finds Vladimir's explanations and pondering tedious, and he feels eager to leave. A few times, Estragon expresses this discontentment and agitation through verbal irony.
For example, when Vladimir brings up the discrepancies in the accounts of the Four Evangelists, Estragon is unwilling to participate in the discussion. Vladimir metaphorically begs him to "return the ball," but Estragon merely comments on the conversation with caustic sarcasm:
ESTRAGON: (with exaggerated enthusiasm). I find this really most extraordinarily interesting.
This verbal irony emphasizes Estragon's dissatisfaction. At this point, just after the play's exposition, the audience may still struggle to distinguish between the two men. As a result, this early instance of divergence provides important characterization. The more cerebral and engaged Vladimir wants to discuss intellectual and religious topics, while the confused and disgruntled Estragon wants to escape such discussions.
After Estragon brings the conversation about the Gospels to an end, the two men seem to be at a loss for what to do next. In his restlessness, Estragon once again expresses his dissatisfaction using verbal irony:
ESTRAGON: Charming spot. (He turns, advances to front, halts facing auditorium.) Inspiring prospects. (He turns to Vladimir.) Let’s go.
In the earlier instance of verbal irony, the stage directions clearly indicate that Estragon is being sarcastic. Here, the stage directions focus on the movement of his body rather than his tone of voice. Nonetheless, it's clear that he doesn't literally find the spot charming or their prospects inspiring. The set is drab, and Estragon has already expressed enough disgruntlement for the audience to know that he's saying the opposite of what he means. Besides, his "Let's go" reinforces that he feels neither charmed nor inspired.
It also seems as though Beckett wants the audience to wonder whether Estragon is critiquing the people watching him. When he says "inspiring prospects" just after turning to face the auditorium, the ironic comment can be interpreted as direct criticism of the people sitting in front of him. In other instances in the play, the characters express some awareness of the fact that they are standing on a stage.