When the leading anti-Semite in Barnard's Crossing, Mass.--a millionaire eccentric--is shot to death, one likely suspect is the president of Barnard's Crossing Conservative Temple, a pushy guy who's been trying to do a real estate deal with the vicious old man. Also likely is the millionaire's unacknowledged, half-Jewish, illegitimate son, who's been oppressed by his father's possessive eccentricities. With two Jewish prime suspects, this must be a case for Rabbi David Small, even though the rabbi stays out of it right till the end because he has his own problems: resisting the women's lib element in the congregation, refusing to perform a purely commercial Bar Mitzvah, worrying if the power-mad synagogue board will vote to renew his contract. Oy. But the rabbi, traditionalism, and Talmudic reasoning triumph as always in the very leisurely, mildly engaging, talky Kemelman manner. The big question: what now for Rabbi Small, with all seven days used up? Washday the Rabbi Got Clean?