Jewish-Themed Tours Include Sabbath Rituals February 06, 1997 Share 1 -- NEW YORK -- Kesher Tours, based here, has been operating Jewish-themed tours to Italy for 19 years. One of the firm's most popular tours combines Italy with Switzerland.The trip begins in Rome with general sightseeing and continues to the Roman ghetto. Friday temple services are followed by a traditional Sabbath dinner, morning services and lunch.In Florence and Venice, the Jewish ghettos also are highlights, as are visits to the Ufizzi Gallery in Florence to see Michelangelo's "David" and the Grand Canal in Venice. After Venice, the tour continues to Switzerland for three days.The 10-night tour is priced at about $2,450, double, including air, accommodations and two meals daily.For details, call (212) 949-9580 or (800) 847-0700; fax (212) 599-6086.Travelers interested in lesser-known Jewish attractions might consider European Incoming Services in Boston, which specializes in independent tours.The firm can show visitors the ruins of Italy's oldest synagogue, 45 minutes outside Rome, or the birthplace of the Italian-Jewish painter Amedeo Modigliani (1884-1920), who hailed from Livorno. European Incoming Services can be reached at (800) 443-1644.