What is the ruling on my friend continuing his work in a maintenance workshop where there is an engineer who curses Allah and His Messenger? And what is the correct way to support Allah and His Messenger in this situation, in light of the Qur’an and Sunnah and the understanding of the Righteous Predecessors?

A Muslim must avoid gatherings where Allah is disobeyed, especially those where Allah and His Messenger are insulted. He must denounce the one who insults and leave the gathering. If he cannot, he must quit working in that place. The best way to uphold Allah and His Messenger is to denounce the one who insults them, explain the gravity of his words, and state that whoever insults Allah and His Messenger is an apostate from Islam. He must also be shunned and boycotted permanently if he does not repent. The employer should be advised to dismiss the one who insults from work if he does not repent.