Rabbi Dr. Dovid Katz of Congregation Beth Abraham of Baltimore is the Joseph N. Muschel scholar-in-residence at Congregation Bnai Yeshurun. During the 8 p.m. oneg, he will discuss “The Battle Between Gracia Mendes and Pope Paul IV in the 1550s.” On Shabbat morning after Shacharit the topic will be “Cossacks and Jews, 1648-49,” and after Minchah at 4:45, he will talk on “Beyond Yeshivish: R’ Yisrael Salanter, R’ Avraham Elya Kaplan and Thinking Out of the Box.” Rabbi Katz, a visiting history professor at Johns Hopkins University, was a contributing editor of the Art-Scroll Schottenstein edition of the Babylonian Talmud. 641 W. Englewood Ave. (201) 836-8916.