Freemasons are expected to exhibit the utmost tolerance both in "Lodge" (the meeting place of a group of Freemasons) and in their daily lives. Freemasonry will thus accept members from almost any religion, including all denominations of Christianity, Judaism, Islam, Buddhism, and so forth. Exactly how far this goes depends on the particular branch or "jurisdiction" of Freemasonry one is dealing with. Deists have traditionally been accepted. In Lodges derived from the Grand Orient of France and in certain other groups of Lodges, atheists and agnostics are also accepted, without qualification. Most other branches currently require a belief in a Supreme Being. But even there, one finds a high degree of non-dogmatism, and the phrase "Supreme Being" is often given a very broad interpretation, usually allowing Deism and often even allowing naturalistic views of "God/Nature" in the tradition of Baruch Spinoza and Johann Wolfgang von Goethe (himself a Freemason), or non-theistic views of Ultimate Reality or Cosmic Oneness, such as found in some Eastern religions and in Western idealism (or for that matter, in modern cosmology). In some other (mostly English-speaking) jurisdictions, Freemasonry is not as tolerant of naturalism as it was in the 18th century, and specific religious requirements with more theistic and orthodox overtones have been added since the early 19th century, including (mostly in North America) belief in the immortality of the soul. The Freemasonry that predominates in Scandinavia, known as the Swedish Rite, accepts only Christians.
Generally, to be a Freemason, one must:
1. be a man
2. believe in a "Supreme Being"
3. be at least the minimum age (18-21 years depending on the jurisdiction),
4. be of sound mind, body and of good morals, and
5. be free (or "born free", i.e. not born a slave or bondsman).
The "sound body" requirement is today generally taken to mean physically capable of taking part in Lodge rituals, and most Lodges today are quite flexible in accommodating disabled candidates.
Freemasonry upholds the principles of "Brotherly Love, Relief and Truth". It teaches moral lessons through rituals. Members working through the rituals are taught by "degrees". Freemasons are also commonly involved in public service and charity work, as well as providing a social outlet for their members. There is considerable variance in the emphasis on these different aspects of Masonry around the world. In Continental Europe, the philosophical side of Freemasonry is more emphasized, while in Britain, North America, and the English-speaking parts of the world, the charity, service and social club aspects are more emphasized.
While Freemasonry as an organization does not directly involve itself in politics, its members have tended over the years to support certain kinds of political causes with which they have become associated in the public eye: the separation of Church and State, the establishment of secular public schools, and democratic revolutions (in the American United States and French France on a smaller scale, but on a larger scale in other places such as Mexico, Brazil, and repeatedly in Italy).
Many organizations with various religious and political purposes have been inspired by Freemasonry, and are sometimes confused with it, such as the Protestant Loyal Orange Association and the 19th century Italian Carbonari, which pursued Liberalism and Italian Unity. Many other purely fraternal organizations, too numerous to mention, have also been inspired by Masonry to a greater or lesser extent.
Freemasonry is often called a "secret society", and in fact is considered by many to be the very prototype for such societies. Many Masons say that it is more accurately described as a "society with secrets". The degree of secrecy varies widely around the world. In English-speaking countries, most Masons are completely public with their affiliation, Masonic buildings are clearly marked, and meeting times are generally a matter of public record. In other countries, where Freemasonry has been more recently, or is even currently, suppressed by the government, secrecy may be practiced more in earnest (again, depending greatly on the particular country). Even in the English-speaking world, the precise details of the rituals are not made public, and Freemasons have a system of secret modes of recognition, such as the Masonic secret grip, by which Masons can recognize each other "in the dark as well as in the light," and which are universally kept strictly secret. (Although these "secrets" have been available in printed exposes and anti-Masonic literature for many years.)
Books You Might Enjoy:
Aristotle - On Dreams
Frater Alastor - Quinti Libri Mysteriorum Appendix
Franz Cumont - The Mysteries Of Mithra
Robert Anton Wilson - Prometheus Rising