Author/professor Benjamin Sommer of the Jewish Theological Seminary is the Adele Rebell Memorial scholar-in-residence at Temple Israel & JCC. After services at 6:30 p.m., he will discuss “What Happened at Sinai, Part 1,” at a dinner. On Saturday, the topic at Muffins & Mishna, at 9 a.m., is “Ten Commandments or Just Two”; services follow. Lunch and learn, at noon, will be devoted to “What Happened at Sinai, Part II.” 475 Grove St. Dinner and lunch reservations, (201) 444-9320 or mnassan@synagogue.org.