Many myths about Masonry have taken hold in the imagination of "conspiracy buffs.” This may be because Freemasons, like government intelligence agencies and big business, often allow the uninitiated to argue amongst themselves so that the truth remains private. In recent years, Masonic organizations worldwide have made efforts to address these myths and better address their critics.

Some of the most common Masonic “fictions” are addressed below:
 

fiction: religion and masonry are incompatible
Opinions about Freemasonry around the world may differ from place to place, but Freemasons always stress non-dogmatism and tolerance. This openness has led to friction between Freemasonry and organizations that hold a negative view of ecumenism, or are themselves intolerant towards other forms of belief and worship.

In general, there are two doctrinal objections to Freemasonry made by established Christian denominations, Catholic and non-Catholic alike:

• The ecumenical nature of Masonic membership is at odds with the claims of exclusivity of belief that distinguish the various religious denominations.
• The "esoteric" aspect of Masonic ritual is seen as synonymous with Gnosticism, declared heretical and suppressed by the early Christian church.

The Catholic Church is openly hostile to Freemasonry, deeming it at least partly responsible for the French Revolution and the resulting decline of the church in Europe – The Knights of Columbus and other Catholic fraternal organizations were established to provide alternatives to Freemasonry for observant Catholics. Although most Freemasons in the English-speaking world are Protestant, some Protestant churches also hold that Freemasonry is incompatible with being a member of a community of Christian faith, based on the scriptural holding that "no man can serve two masters".

The 1917 Code of Canon Law explicitly declares that joining Freemasonry entailed automatic excommunication; the revised Code issued in 1983 does not explicitly name Masonic orders among the secret societies condemned in canon 1374. According to some interpretations of canon law, Roman Catholics are forbidden to become Freemasons by their church, though Freemasons do not bar Roman Catholics and it is not unusual to find Catholic members. The Eastern Orthodox Church forbids its members from being Masons. Freemasonry is also discouraged by some denominations of Protestantism. The Free Methodist Church continues to prohibit its members from also joining societies such as the Freemasons. The Southern Baptist Convention, the largest association of Baptists in the United States, also stated that participation in Freemasonry is inconsistent with its beliefs.

This form of criticism has been markedly reduced, since modern nation states like the USA and Europe in general are founded on religious tolerance, and many adherents of the religions that formally opposed Masons now believe in the main Masonic principles.