ArgumentThe main thesis of this paper is that Copernicus's avoidance of all admission that scripture was contravened inDe revolutionibusand his composition of its new Preface in 1542, as well as the non-publication of Rheticus'sTreatise on Holy Scripture and the Motion of the Earth, were influenced by the early information they received on the failure of the 1541 Regensburg Protestant-Catholic colloquy, among the major consequences of which were significant increases in the problems concerning publishing works which contravened scripture. This is supported (...) by examining Rheticus's first letter to Paul Eber in conjunction with the documents on the Regensburg colloquy and on censorship in Nuremberg, as well as with the existing literature on Copernicus and his context. In view of the main thesis, Copernicus's apparent dedication of the work to the Pope merits additional explanation, and the second thesis is that components of explanations for several aspects of those parts of the Preface that relate to the Papacy and to theologians can be provided via comparisons with previous diplomacy between Warmia and the Papacy which occurred or was being referred to during Copernicus's time. This is supported by examining these parts of the Preface in the light of a selection of the relevant documents. (shrink)