“How can a doctrine be essential in a religion if the founder of the religion never mentions it, or teaches his apostles to pass it on?”

Preface (Scribner edition, 1872) <!-- New York, Scribner p xxiii - xxiv -->
Chips from a German Workshop (1866)
Context: If there is one thing which a comparative study of religions places in the clearest light, it is the inevitable decay to which every religion is exposed. It may seem almost like a truism, that no religion can continue to be what it was during the lifetime of its founder and its first apostles. Yet it is but seldom borne in mind that without constant reformation, i. e. without a constant return to its fountan-head, every religion, even the most perfect, nay the most perfect on account of its very perfection, more even than others, suffers from its contact with the world, as the purest air suffers froln the mere fact of its being breathed.
Whenever we can trace back a religion to its first beginnings, we find it free from many of the blemishes that offend us in its later phases. The founders of the ancient religions of the world, as far as we can judge, were minds of a high stamp, full of noble aspirations, yearning for truth, devoted to the welfare of their neighbors, examples of purity and unselfishness. What they desired to found upon earth was but seldom realized, and their sayings, if preserved in their original form, offer often a strange contrast to the practice of those who profess to be their disciples. As soon as a religion is established, and more particularly when it has become the religion of a powerful state, the foreign and worldly elements encroach more and more on the original foundation, and human interests mar the simplicity and purity of the plan which the founder had conceived in his own heart, and matured in his communings with his God. Even those who lived with Buddha misunderstood his words, and at the Great Council which had to settle the Buddhist canon, Asoka, the Indian Constantine had to remind the assembled priests that "what had been said by Buddha, that alone was well said;" and that certain works ascribed to Buddha, as, for instance, the instruction given to his son, Râhula, were apocryphal, if not heretical.

As quoted in The Life of Florence Nightingale (1913) by Edward Tyas Cook, p. 392

Source: Broca's Brain (1979), Chapter 23, “A Sunday Sermon” (p. 338)

Letter to Humphry House (11 April 1940). The Collected Essays, Journalism & Letters, George Orwell: An Age Like This, 1920–1940, Editors: Sonia Orwell, Ian Angus.  p. 530 http://books.google.com/books?id=0j2qODEJkdoC&pg=PA530#v=onepage&q&f=false.

Source: Agnes Grey

Source: Guide for the Perplexed (c. 1190), Part III, Ch.20
Context: Consider in how many ways His knowledge is distinguished from ours according to all the teaching of every revealed religion. First, His knowledge is one, and yet embraces many different kinds of objects. Secondly, it is applied to things not in existence. Thirdly, it comprehends the infinite. Fourthly, it remains unchanged, though it comprises the knowledge of changeable things; whilst it seems that the knowledge of a thing that is to come into existence is different from the knowledge of the thing when it has come into existence; because there is the additional knowledge of its transition from a state of potentiality into that of reality. Fifthly, according to the teaching of our Law, God's knowledge of one of two eventualities does not determine it, however certain that knowledge may be concerning the future occurrence of the one eventuality.

Homecoming saga, Earthborn (1995)