Faith and spirituality are open-source. The core doctrines of any respectable faith can be acquired from the community of practice at either no charge, or at very near the cost of publication. While supplemental literature and the like is often sold by members of that community in a profitable fashion, the core doctrines and texts are made as available as possible. Scientology does not treat its core doctrines in such a fashion; it sues and issues take-down notices to those that openly share it’s central belief system.
Many of the core beliefs of Scientology are not available until after progressing within the organisation, investing capital, and otherwise changing one’s life. Which places an unfair and unwarranted pressure on the membership - those who do not choose to believe the doctrine after it is revealed will unravel the life that they have invested in the organisation. This is not true of healthy communities of faith; while you may not know everything “going in”, the concealment is not active; if you ask, you will be told
Scientologists are isolated from society informationally (they are not to read some books and websites; a net-nanny is often used to further this isolation), linguistically (scientology is loaded with words altered from common use, making communication difficult), socially (through 'disconnection', the practice of breaking relations with anyone in their lives that criticizes Scientology itself), and sometimes physically (through varied means including closed camps and the “sea org”)
Video Reference: Jenna Miscavige, the niece of David Miscavige, discusses isolation and disconnection.
At each and every level of scientology, a member is promised specific benefits. In order to obtain those benefits, however, the member must take part in regular activities, express themself in specific ways, and must be able to pass what amounts to a cheap lie detector test while showing that they are doing so. There’s no option to stand up during the hymns and mumble “rhubarb, rhubarb” in order to fit in; if you can’t twist your mind into imagining ridiculous and contradictory situations (breaking down your viewpoint of what is and is not real), without showing tension on the E-meter, you cannot progress.
Above and beyond charging for knowledge of doctrine, Scientology also charges ridiculously high prices for simple electronics (the e-meter), offers actual comissions for introducing new converts (leading to many cries of “pyramid scheme!”), and charges inte ally for the basic and most common practice of the faith - the action of auditing. These charges are not negotiable; they are “fixed donations” which are required. You try telling a Muslim that he needs a special $500 compass to point the direction he should face for prayer, or proposing to the Catholic church that they should install “holy water dispensers” at the door, at a dollar a shot. See how far you get.
Hearing Tom Cruise say that when a Scientologist sees a car accident, “you’re the only one that can really help” is merely the tip of the iceberg. Scientologists are trained to respond to disasters and crises by using them as centers for recruitment. They are further trained to honestly believe that this IS a way of helping, which means that opposition on this point paints the person in opposition as ignorant in the mind of the Scientologist. This differs from other communities of faith significantly - while you might need to listen to a sermon to get your soup at a fundamentalist soup kitchen, at least the soup is real.
Even in the general press, Scientology is described as “Famously litigious”. Anyone that takes the time to look further will discover numerous examples of “fair game”, an express policy of actively seeking to not only silence critics, but ruin their lives. L.Ron Hubbard described legal practices as a useful way of bludgeoning critics into silence. Amending doctrine within Scientology is considered “squirreling” - a major offense. In short, the organisation is hostile to criticism of any sort, for any reason at all, to a degree that is not considered acceptable in any other community of faith.
Reference: A list of scanned Cease-and-Desist letters issued by the Church of Scientology Video Reference: David Miscavige “clearing things up” on Nightline, in 1992
The CCHR lobbies to disrupt psychological practice on behalf of Scientology; Narconon preaches drug rehabilitation on their behalf, WISE promotes their version of business management. Scientology won a tax-exempt status that is better than that of other faiths by harrasing the IRS in court for over ten years. The overall organisation of Scientology works under so many names and towards so many purposes, and so many of them plainly for gain, that exposure to it often causes the reaction of “This is too strange. It’s like a B-movie conspiracy brought into reality”. And in many ways, this is one of their significant defenses - it’s just so very mind-boggling, and the reporting so tinfoil-hat sounding, that it seems unbelievable. Yet it remains true.
Video Reference: David Miscavige, adressing their 2007 summit regarding “efforts to stop psychiatry.” Video Reference: A CCHR anti-psychiatry ad, themed around “school shootings.”
Scientology teaches that by reaching sufficient levels within their practice, and by “making your own reality”, a member can overcome illness by will alone. It teaches that mental instabilities caused by chemical imbalance, and illness, should generally be treated with vitamins and audiiting rather than medication - including, in several cases, schizophrenia and cancer. People die as a result of following these teachings - and, as icing on the cake, remember that last point; Scientology lobbies to ruin the reputations and practices of those that would prescribe such medications and offer clinically tested and peer-reviewed treatments.
The practice of “auditing” can be likeled to the confessional or the psychiatric couch in so far as it is a place where memebers share personal experiences, often intensely private and painful ones, in order to alleviate problems (granted, methodology of “how the relief comes” are radically different). However, unlike psychiatry and the confessional, the controls on this information are neither strict nor scrupulous. For a priest to break the seal of the confessional is a shocking and horrible thing from a Catholic viewpoint. For a psychiatrist to blather about patients by name is worthy of a lawsuit. No such controls exist on the Scientology practice; “peeking” at the file of someone below you is fairly common.
Video Reference: News article and interview