What is the ruling on a Muslim taking a salary for teaching Islamic knowledge?

It is permissible to take payment for teaching Islamic knowledge. Al-Khatib al-Baghdadi mentioned that it is incumbent upon the Imam to allocate from the Muslim treasury a sufficient stipend for anyone who dedicates himself to teaching Fiqh (Islamic jurisprudence) and giving fatwas, so that he is not forced to seek other professions. If there is no treasury, or if the Imam does not allocate anything, it is permissible for the people of the town to provide him with an allowance from their own money so that he can dedicate himself to giving fatwas. The permissibility of taking payment for leading prayers (Imamah) and teaching the Quran has already been established.