Abu Dhayyaal said, ”Learn to keep quiet just as you learn to speak. If it is that speech is to guide you, then indeed silence protects you. You have two qualities in silence: A quality through which you take knowledge from one who is more knowledgeable than you; and a quality through which you repel the ignorance of one who is more ignorant than you.
[Fadlul Ilm by Shaikh Raslaan page. 283]