JERUSALEM — It was 8 on a Thursday night, two hours before downtown Jerusalem would erupt into early weekend revelry, and Rabbi Shmouel Semelman, 59, was making his rounds.

Others his age were enjoying early meals before the rowdiness began. But it is the rabbi’s duty to ensure that any establishment in Jerusalem, and its surrounding area, displaying a kosher certificate is serving only alcohol that is certifiably kosher.

Rabbi Semelman is the director of the Department of Alcoholic Drinks for the Jerusalem Rabbinate, and a world-renowned arbiter of the exemptions granted (or denied) to beverages that do not bear standard kosher certification. The rabbi, who has been conducting inspections at least once a week for about 12 years, is authorized to remove any offending bottle on the spot.

On his website, kosherliquorist.com, the rabbi serves as an oracle for anxious observant Jews who write him asking about the kosher status of obscure Belgian wheat beers or fashionable boutique gins.