a. Moreover, this article is no doctrine or fixture (auff satz) dreamt up by men apart from Scripture, but is clearly established and founded in the Gospel through luminous, pure, undoubted words of Christ, and has been unanimously believed and held in all the world from the outset of the Christian church to this hour, as is proved by the books and writings of the dear Fathers of both Greek and Latin language and also by daily custom and the work of experience to this hour. This testimony of the entire holy Christian church (assuming we had no more than it) should alone suffice to attach us to this article and to move us neither to hear nor to tolerate any factious spirit on this matter. For it is a perilous and dreadful thing to hear or believe anything against the unanimous testimony, belief, and doctrine of the entire holy Christian church.
b. It would be a very dangerous to conclude that for so many hundreds of years the Church across all of Christendom did not have the right understanding of the sacrament.
Martin Luther
a. Letter to Duke Albrecht of Prussia, 1532
b. Opinion of 17 December 1534