Taamei haMitzvos
Until adultery became too commonplace (in the days of Rabbi Yochanan Ben Zakai, shortly after the destruction of the Beis haMiqdash) a wife whose husband suspected her of having an affair could forbid her from secluding herself with that man. If they are caught in seclusion, she is brought to the Beis haMidqash where a kohein would write the relevent...