Temple Adas Israel in Sag Harbor Village, the oldest synagogue on Long Island, is marking its 120th anniversary this year. Members, guests, and dignitaries will gather for a celebratory dinner on Sunday at Osteria Salina in Wainscott. Rabbi Daniel Geffen will serve as master of ceremonies, and speakers will include Neal Fagin, president of the congregation, and Ronald Lauder, a Wainscott resident who is chairman emeritus of the Estee Lauder cosmetics company and a member of Adas Israel.