The one who is filled with conceit cannot perceive their own faults. Among the consequences of conceit is that it leads to detesting the thing that caused conceit in the first place. This is because the one who possesses conceit regarding a matter, does not increase himself in it to better himself, rather he advances to find fault in others.
The cure for conceit is to know one’s faults, and to ask other people about one’s faults, and to reflect on the state of those that preceded you who were also conceited. Therefore if for example, a scholar has conceit regarding their knowledge, they should read the biographies of scholars who preceded them. This is a reminder not to be proud of oneself, as there is always someone who is, or was, better than you.
When we reflect on the lives of those who came before us in Islam, we see that we are like a person who has one dinar. We are so happy with it, and yet there are people who have thousands and thousands of dinars, people’s whose knowledge and practice of Islam was thousands of times better than our own. That is a truly humbling thought.