 Frank served on this Beth Din for nearly 60 years, eventually becoming "Av Beit Din" (head of the rabbinical court) and Rav of Jerusalem.Frank was active in establishing the office of the Chief Rabbinate of Israel and was instrumental in appointing Rabbi Abraham Isaac Kook as the first Ashkenazi Chief Rabbi.Rabbi Jacob Meir, the first Sephardic Chief Rabbi, had been in Palestine prior to the formal development of the office.