“Able to teach” means an effective Bible communicator in a group setting — practical, accurate, clear, and engaging with at least a small group. Not “able to wow an auditorium.”
“Husband of one wife” means a one-woman man. Men who have experienced divorce are considered case-by-case.
“Faithful children” means the man has raised obedient, honorable children — with the specifics of each man's life considered case-by-case.