Shaykh Abdul-Muhsin Al-Abbaad was asked:
Is it correct for a student of knowledge to wear pants?
No, rather the Thawb or the Qamees is the clothing of the Muslims. Thus, the Muslim should wear it in whereever he may be. That which isn’t befitting is that he be in a land and he comes with a clothing which is strange to the people, and he is famous/known due to it. If the clothing is a legislative clothing such as the Qamees, then he doesn’t take it off because the Qamees is legislative clothing. It is also not befitting for the individual to wear the clothing of the disbelievers, it’s not correct for the individual that he wears the clothing of the Europeans.
Majid Jawed Al-Afghanee