Does refusing to teach people fall under concealing knowledge?

Question:
In some cities, there are people who studied under many famous scholars known for their knowledge and piety. When young people today ask them to sit and study under them, they refuse. Does this action count as concealing knowledge? And do they sin by not conveying to people what they have learned? I ask for clarification on this.

Answer:
I believe that it is obligatory for them, whenever it is easy for them to find someone to read to them, to do so according to their ability, at appropriate times. It is obligatory for them to teach people from what Allah has given them, and to convey to people what Allah has given them, and not to conceal it. Rather, it is obligatory for them to teach people, and people are in need. Teaching knowledge is a collective obligation (fard kifayah), and the collective obligation is not currently being fulfilled—there is no one fulfilling the collective obligation—neither in Riyadh nor elsewhere. Therefore, the need to teach knowledge is pressing.
It is obligatory for scholars, wherever they are, to teach and to guide people if it is easy for them to find someone to learn, even through radio, or even through the press.