See the Bulletin of the Atomic Scientists, 8 (1952), p. 143-6, 165 for a translation of part of the Papal text. For an excellent discussion of it 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.