See Ernan McMullin, "How should cosmology relate to theology?" in The Sciences and Theology in the Twentieth Century, A. R. Peacocke, ed. (Notre Dame: University of Notre Dame, 1981), p. 17-57. According to McMullin, the Pope later refrained from this claim after being cautioned by Georges Lemaitre. Though a Roman Catholic Priest and one of the founders of Big Bang cosmology, Lemaitre’s view was "two worlds": keep theology and science entirely separate. See also Southgate, Deane-Drummond, et al., God, Humanity and the Cosmos, 122-23.