Gregor's feelings about his job as a traveling salesman are made clear very early in Part I of the story. He hates it for numerous reasons:
God! . . . What a job I've chosen. Traveling day in, day out. A much more worrying occupation than working in the office! And apart from business itself, this plague of traveling: the anxieties of changing trains, the irregular, inferior meals, the ever changing faces, never to be seen again, people with whom one has no chance to be friendly. To hell with it all!"
Even though Gregor despises his job, he continues to work because his parents owe Gregor's boss money. He plans to quit the miserable job when he has saved enough money to pay his parents' debt--in five or six years.
At the beginning of The Metamorphosis, Gregor explicitly mentions that he detests his job as a traveling salesman. He says:
"There's the curse of traveling, worries about making train connections, bad and irregular food, contact with different people all the time so that you can never get to know anyone or become friendly with them. It can all go to Hell!"
He goes on to say that he hates getting up early and that he never gets sufficient sleep. He stays at his job, however, because his parents' owe his boss money, and he needs to protect his parents and his sister. He thinks that in five or six years, he will quit his job, once he's paid off the debt.
Although he has already turned into a "horrible vermin," Gregor attempts to get out of his bed because he's afraid of being late to work. As he struggles to get out of bed, the chief clerk from his office comes around to his parents' house to check why Gregor did not get on the train as he was supposed to. The narrator says,"Why did Gregor have to be the only one condemned to work for a company where they immediately became highly suspicious at the slightest shortcoming?" Gregor wonders why his employer doesn't trust him and why they consider him unfaithful when he works so hard. Becoming upset at his employer's immediate suspicion, he is finally able to rouse himself, as a bug, out of bed, and he falls on the floor. When the chief clerk continues to hound him, Gregor is finally able to open the door to his room. The clerk sees that Gregor has turned into an insect, and he runs away.
Gregor dislikes his job with an intensity that appears nearly obsessive. He reflects on his feelings about his job, his boss and his co-workers early in the story when he awakes in bed.
Gregor's first thoughts about the hassles presented by the travel required in his job end with the phrase, "To the devil with it all!" Indeed, Gregor's transformation now makes working impossible. However, Gregor's whole sense of self and sense of normalcy is wrapped up in his bitter position at work. Despite his new condition, he tries to go to work, worrying over the prospect of missing a day.
The breach between Gregor's fantasies of quitting and his attachment to his normal work-life is never explicitly articulated, but the ineffectual and self-pitying Gregor certainly dreams of resigning and telling off his boss.
"If I didn't hold back for my parents' sake, I'd have quit ages ago. I would go to the boss and state my opinion out loud from the bottom of my heart. He would've fallen right off his desk!"
Consoling himself with thoughts of a future where he will no longer work as a traveling salesman, Gregor uses the consolation as a way to convince himself to get up and go to work and face another day.
The debt that his family owes provides one formal reason that Gregor feels he cannot quit the job he dislikes so much, but his reflections also suggest that Gregor fears his boss as much as he despises him. Again, this dynamic is only implied in the text, although Gregor's passive fantasizing should be familiar to readers as a common mode of powerless and internal resistance to economic pressures on the lower and middle classes. Gregor and his fantasy, in other words, fit neatly into a typical category of class-based resentment as rendered in literature.
This information, both that which is overtly stated and that which is implied, in delivered via Gregor's quoted thought and un-quoted material intended to represent his thinking. The narration utilizes a degree of omnipotence in this regard. Situated as a narrative voice outside of the character, the narrative voice nonetheless has full access to Gregor's thoughts and feelings.