A divorce between the world of business and the world of faith is a recipe for disaster, according to an ethicist who will give a free public lecture Tuesday at Belmont University. The Rev. Robert A. Sirico, who co-founded the Mission of the Acton Institute in Grand Rapids, Mich., in 1990, will speak about “The Entrepreneurial Vocation” at 4:45 p.m. Tuesday. He was invited to Nashville by the university’s Center for Entrepreneurship and Center for Business Ethics.