In 1738, Pope Clement XII declared Freemasonry an excommunicable offense, and the Catholic Church's position hasn't softened much since then. The Vatican this week confirmed its ban on Catholics becoming Freemasons, a secretive and ritualistic society with an estimated 6 million members worldwide. "Active membership in Freemasonry by a member of the faithful is forbidden because of the irreconcilability between Catholic doctrine and Freemasonry," the Vatican's doctrinal office wrote in a Wednesday opinion that was signed by Pope Francis.
The National Catholic Register explains that irreconcilability, citing Freemasons' belief in "indifferentism, or the position that a person can be equally pleasing to God while remaining in any religion, and a deistic concept of a 'Great Architect of the Universe.'" The opinion referenced a 1983 declaration—signed by the late Pope Benedict XVI, who was then the Vatican's doctrine chief—that said Catholics "in Masonic associations are in a state of grave sin and may not receive Holy Communion," per Reuters. That outlet reports that the Vatican published the opinion after a bishop from the Philippines grew concerned about a rising interest and membership in Freemasonry there.
Freemasonry dates to 1717, when the first Grand Lodge was established in England. The United Grand Lodge of England calls modern Freemasonry "one of the oldest social and charitable organizations in the world." Fox News notes its members swear oaths of secrecy, fellowship, and fraternity, and that there exists a "vast catalog of rituals, ceremonial attire, and secret signals between Masons. These aesthetic affectations often use Christian imagery despite being used for non-Christian rituals." (More Freemason stories.)