I was asked a few times to elaborate on what I meant by this statement and while I meant it as a quip originally, I do have some thoughts on this with regard to the "jump off point" provided by Herr Guy here
It starts off with "Late Jhanas are weird because1 they demonstrate you can inhabit ABSTRACT states" his amazement here being the function of "embodying abstraction" via your conscious experience. My quip, "It is interesting how the Jhana frame gatekeeps tantra and makes it opaque, is in reference to the flat absurdity of Herr Guy's comment here. We can assume Herr Guy has been doing Jhana for awhile, he likely has heard of it for even longer, it is of course a mainstay of "tpot" ritualism, yet he still, years after first likely interacting with this idea, shows amazement at the fact that "you can embody abstract states". This amazement encapsulates something that I've always complained about "tpot" brand Theosophy, the inability to explain the function of things while solely focusing on the practice and spectacle. Always forgetting that function precedes form. What do I mean by this? Let me explain blunty--
Jhanas are a form of 'Tantra' which is just the Sanskrit word2 for what we in English might call 'Magic' or earlier might have called 'Sooth' (Like a Soothsayer3), technically Jhanas are not actually a form of Tantra epistemologically, but when you look at the function they provided they are doing essentially the same thing. You can bake wheat, eggs, and sugar in various ways to get a multitude of different deserts, but ultimately, functionally speaking, you are just making different kinds of bread. The 'eigen-tantra', or as I'd prefer to call it, Ur-Sooth, that we're dealing with here is the basis for ALL ancient esoteric magic systems, and in a proper education on these subjects, is instructed to you pretty much immediately.
This ur-sooth is essentially the idea that, simply put, abstractions are real, abstractions are alive4, we control them and shape them and embody them, and we can use our free will offered by the awesome and terrific power of our minds to mold them to our bidding. The point of Jhana states is to embody states of abstractions, simply put5, yet no introduction to Jhanas will say that, they won't say "The point of Jhana meditation is to become possessed by certain kami", but that is what it is, and this is the essential function of Tantra as well, it is also how you do divination like Tarot or Iching6.
The idea of kami is the7 best functional description of what abstractions are, in Tianmu we call them 'Ghosts', in Hinduism and Buddhism they call them Devas or Asuras8, but ultimately the function here is the same. There are abstractions, they exist, and humans interact with them and change them from our relationships with them.
Jhana meditation is basically a form of deity yoga (devatayoga)9 and this concept can be applied to so many other things outside of the narrow Jhana framework.
In my research I studied New Age cults and how they often monopolize and territorialize esoteric folk practices, the way that Jhana is framed where the 'function' of it is essentially ignored or glazed over in favor of the benefits, the spectacle, provided in hand with "Jhana retreats" and other money making schemes, reminds me a lot of how Sukyou Mahikari pretends that10 they invented "qigong" and that only they are capable of doing it, and in doing so, strip away all of the deep folk history of qigong11 in favor of a very narrow outcome based understanding that can only be preformed through the correct rituals under the proper authoritative guidance.
So, with all of this context it is easy to explain what I mean now. Jhana meditation is real, and does something real, but it is something that is not exclusive to Jhana or any other esoteric tradition, you can meditate on kami/ghosts/abstractions/ideals/gods/daemons all you want, and it is a real thing, you don't need the Jhana framework to understand it, when we do Jhana we are just embodying states of abstraction, we focus on a narrow range of abstractions like happiness, contentedness, and fall into them. This can be done for everything, from concepts like Liberty, to Love, to even Envy or Hate. Many people in fact live their lives day by day doing the 'function' of Jhana meditation with things that only make them miserable, think about lookism culture, that is what it means to be 'possessed by a demon12'.
To anyone who understand kami and yoga outside of the Jhana framework the "OMG I just realized Jhana is embodying states of abstraction!" comment is hilarious because it is like being blindfolded and being taught how to ice skate without knowing that is what you are being taught and then saying "Wow if I move my legs like this, I start gliding" of course you are, you're ice skating, that is what you are doing. Take the blindfold off, the frame limits your understanding of what is and isn't possible. Apply the function of Jhana to everything in your life, this is what it means to 'be mindful'.
As one last aside, I want to say that I actually do think Jhana meditation is cool and real, my critique here is in the narrow frame which is so prevalent on "tpot" (peace be upon them), if you're interested in some of the neurological research on Jhana studies (and with this expanded knowledge, the implications they have on yoga/meditation at large) feel free to watch this lecture from the University of Virginia: https://t.co/rbfshlxG8R
It is an incredibly fascinating and interesting lecture and I recommend anyone interested in this stuff to watch it. Thank you and Good Yule