Thirty spokes share the wheel's hub;
It is the center hole that makes it useful.
Shape clay into a vessel;
It is the space within that makes it useful.
Cut doors and windows for a room;
It is the holes which make it useful.
Therefore profit comes from what is there;
Usefulness from what is not there.
(trans. Gia-fu Feng & Jane English)
Here -- in verse 11 of the Daode Jing -- Laozi reminds us that the usefulness of a door (or window or pot or wheel) is in the space, the emptiness that it frames. And it is for exactly this reason that doorways are frequently used as a metaphor for a passageway to spiritual freedom:
If our deluded egoic bondage is the cage we're currently in -- then its doorway allows a passage out of that cage, into the open space, the endless sky of liberation.
If we've been traipsing endlessly through the desert of samsara -- thirst unabated, continually succumbing to the false promises of lake-mirages -- then the doorway we pass through is into the refuge of "our Father's mansion": the spiritual estate of our True Home.
So the doorway metaphor can work either way: signifying a passage into freedom or a passage out of bondage. In either case, for the doorway to function as such, it must retain its openness -- and be related to as a passageway, not reified as a destination, in and of itself.
Do you remember the movie, Shawshank Redemption? Lots of violence -- which I don't usually go for, in a movie -- but in the service of a truly uplifting finale, and some deep contemplations on the meanings of freedom and bondage. Anyway, what was the main character's very unlikely doorway to freedom? A Raquel Welch poster! -- whose visually-enticing sexuality, on its surface, contributed to making it the perfectly-clandestine gateway, since none of the guards thought to look behind that external representation of a sex-symbol, for the tunnel-to-freedom, years in the making ....
Or how about the invisible doorway, in the Harry Potter movies -- through the seemingly impenetrable brick wall in the subway station -- which opened to its secret platform, used to catch the Hogwarts Express: the train to Hogwarts Castle that Harry Potter and his classmates used, at the beginning of each semester, to enter a completely different wizard-world?
So there are hidden doorways like this (the Raquel Welch poster and the Harry Potter brick-wall) -- available only to those few who know their secret location. And then there are spiritual organizations, with their various technologies, which present themselves as more public doorways: available to any and all who choose to enter. And what we notice is that -- although the usefulness of a doorway is all about the open space that it frames -- the frames themselves can and do vary widely ....
Some of the frames, and their corresponding doorways, are extremely high-maintenance and ornate: so much so, in fact, that the doorway opening either disappears or becomes almost impossibly difficult to locate, amidst the bric-a-brac; or the frame is so enticingly gorgeous that it becomes nearly impossible to resist the temptation of stopping to polish, bow and venerate; or so vastly intricate that it becomes oh-so-easy to detour left or right, following -- for years, decades, lifetimes -- the endlessly-expansive door-frame designs, curling outward like an infinite Mandelbrot Set.
Some frames are irresistibly attractive in potentially dangerous ways: sticky as fly-paper, or so potently magnetic that any little piece of metal you might be carrying (car-keys, braces on your teeth, a stainless-steel necklace) will draw you like so many iron filings, into a nearly-inescapable attachment to the frame.
Others are so purely functional and matter-of-fact -- so transparent as to render them (if not entirely "hidden" or "secret") nearly invisible, very easy to miss.
So, what's more important: an affinity for the frame, or its capacity to ferry us -- through its openness -- to freedom? Hmmmm ......