There is some difficulty in separating fact from fiction in the specific nature and especially exact origins of most religions. It may help frame our thinking and tune a healthy skepticism if we begin with a bland definition of religion, before noting the more acerbic statements by some, of its connections to mythology and legend.
Miguel de Unamuno in his Tragic Sense of Life (1913) states that "Religion consists in the simple feeling of a relationship of dependence upon something above us and a desire to establish relations with this mysterious power." This contains the valid assumptions that religions are derived from the human mind and that many people seek a feeling of security and direction from a supernatural being. Religious beliefs typically stem from elements of mythology and legend as have been reviewed in recent times and in scholarly fashion by Joseph Campbell, whose talks are recorded on video tapes, and by Kenneth Davis who has put together DVDs on mythologies from ancient times and disparate peoples. I should like to remind everyone that these interesting stories, even though they have been, and in some cases still are, the bases of religions, have varying content of verifiable facts. Some comments on this point are worth noting:
Joseph Campbell in The Hero with a Thousand Faces (1949) writes that "Mythology is defeated when the mind rests solemnly with its favorite or traditional images, defending them as though they themselves were the message that they communicate. These images are to be regarded as no more than shadows from the unfathomable reach beyond."
Typical of the in-your-face writing of Ambrose Bierce, he defined mythology in The Devil's Dictionary (1958) as "The body of a primitive people's beliefs concerning its origin, early history, heroes, deities and so forth, as distinguished from the true accounts which it invents later."
Walter Lippmann noted in Public Opinion (1922) that "What a myth never contains is the critical power to separate its truths from its errors."
A harsh conclusion from the before-given statements caused James K. Feibleman to write in Understanding Philosophy: A Popular History of Ideas (1973), "A myth is a religion in which no one any longer believes."
An even more critical definition by Laurence J. Peter given in Peter's Quotations: Ideas for Our Times (1997) is "Legend: A lie that has attained the dignity of age.
The bottom line is as stated by Oscar Wilde: "Truth in matters of religion, is simply the opinion that has survived." A gentleman raised in the ethos of Unitarianism, Ralph Waldo Emerson, took a more humorous view that "The religion of one age is the literary entertainment of the next."