Hazrat Shaikh Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) once mentioned:
My beloved brothers! I wish to say a few words which I continue reminding people about. It is an established fact and often mentioned by our elders that a student who disrespects his Ustaaz will always remain deprived of the ‘ilm of deen (deeni knowledge). To the extent you respect your Ustaaz you will be successful in attaining knowledge. During my childhood days I recall the time where even after qualifying and holding prominent government positions, non-Muslim students would be seen showing respect to their Muslim teachers and Muslim students would be seen showing respect to their non-Muslim teachers. Whether a person held the position of a judge or a mayor, as soon as he would see his Ustaaz, he would immediately stand up out of respect and reverence for him.
Beloved brothers! We need to once again acquire these qualities of adab and respect. It seems like over the last 50 years these qualities are gradually diminishing in the Ummah. (Malfoozaate Hazrat Shaikh 1/36)