Is it obligatory for the questioner to leave his job due to being humiliated by the employer, knowing that his financial situation is difficult and he is in debt?

The owner of an establishment has the right to command and prohibit within it, but he does not have the right to harm others. His claim that he fears God does not align with his statement that he does not allow anyone to describe anything he possesses as permissible or forbidden, and that everything is left to his discretion. This is not befitting a young man described as fearing God.

Islam calls for humility and prohibits arrogance. The Prophet, peace and blessings be upon him, said: "No one who has the weight of a mustard seed of arrogance in his heart will enter Paradise," and "Indeed, Allah has revealed to me that you should be humble, so that no one boasts over another." Arrogance is "rejecting the truth and belittling people," meaning pushing it away and denying it, and despising people.

If these insults cause you stress and health disturbances, you should leave this job, because maintaining health is obligatory. Your colleagues should inform the employer of your condition and persuade him to avoid harming you. Sustenance is in the hands of Allah and must be an unchangeable part of a believer's creed.