Do OPC churches require those who teach Bible studies or classes to have the spiritual gift of teaching? Or can anyone who seems to be qualified teach?
In terms of teaching outside the formal Lord's Day services, there is a great deal of liberty given to the local sessions. Ordinarily it would be given to ministers and elders to do the teaching in a mid-week Bible Study, for example. However, each session is given the responsibility to discharge that ministry as they see fit. Certainly a man who teaches in this capacity ought to be "apt to teach." He ought to be known for handling rightly the Word of Truth and such teaching should always come under the oversight and scrutiny of the session. But to answer your question more directly, there are no formal procedures one must go through in order to be assigned the task of teaching a mid-week Bible Study. It is left to the discretion of the local session.