Shaykh Mohsin Al-’Abbaad: Being preoccupied with warning and being engrossed with the people and [with], ‘What do you say about so and so? What do you say about so and so? Should so and so be warned against? So and so is not to be warned against,’ ya’ni, all some people know is warning, busying themselves with warning—whilst not knowing a thing about the most rudimentary aspects of knowledge—he only busies himself with issues such as these.

So it is not fitting that a Muslim’s concern be to speak about people or to ask about statements made about people, and that his sole preoccupation be connected to people. He should busy himself with knowledge and should not let his tongue loose concerning the people.

Yes, it is possible to warn against a person whose evil, disobedient sinning, and harm has become apparent, but not everyone who makes a mistake or who slips up is to be warned against—because if that were the case there wouldn’t be anyone who is not warned against! And who is there who has never sinned? And who is there who has good deeds only?

Questioner: … some people drop certain Shaikhs for [particular] issues, like if that Shaikh has definitions [which he uses] which this other person sees as incorrect, or the Shaikh has a certain way of teaching which he sees as incorrect?

Al-’Abbaad: Whatever the case, a person must guard his good deeds and not squander them, he must not distribute them amongst the people, but must guard them for himself and leave off busying himself with people and warning against them, he must preoccupy himself with beneficial knowledge, teaching it if he is qualified to teach and if not, then he learns.

Taken from http://giftsofknowledge.net/category/methodology/