Moon Days, and Where They Actually Came From

We do not practise on the new moon or the full moon. Ask why and you will get the same answer everywhere, in almost the same words: the full moon is prāṇa, the end of the inhalation, light and upward and ungrounded; the new moon is apāna, the end of the exhalation, heavy and downward and disinclined to move.

It is a good answer. It is memorable, it maps onto something you can feel in your own breath, and it has been repeated so many times on so many studio websites that it now reads as doctrine.

I went looking for where Guruji said it.

First, what is not in doubt

Pattabhi Jois kept moon days, and he taught that they mattered. That is not a thin claim and nothing below is meant to blur it.

It is attested by the people who were in the room. Senior students who spent decades in Mysore say without qualification that the shāla closed on amāvāsyā and pūrṇimā, that this was not a suggestion, and that Guruji spoke about those days in terms of energy — that the body is differently disposed on them, that injury comes more easily, that you do not push. The interviews collected in Guruji are where most of that testimony sits, and it is consistent across teachers who agree about very little else. The observance is also still institutional: the lineage's own shāla in Mysore publishes a Holidays / Moon days page today. It did not weaken after Guruji died.

So when this page says the rationale cannot be traced to him, it means something narrow, and it should be read narrowly: the particular prāṇa/apāna paragraph everyone quotes is not his words. It is not a claim that he was indifferent to moon days, that the observance is a misunderstanding, or that his own reason was merely administrative. He kept them, he meant them, and by every account he gave an energetic reason for them. What we do not have is him giving it in a form anyone can quote.

He did not write it down, and that proves less than it looks like

It is not in Yoga Mala, his only book. The one place that book takes up lunar timing is a passage on brahmacharya — when to have intercourse if you want children — and it says nothing about āsana.

It is not in Krishnamacharya's Yoga Makaranda either, the 1934 text this whole lineage descends from. Moon days are simply absent.

The wording everybody quotes — prāṇa at the top of the inhalation, apāna at the bottom of the exhalation — traces to a short essay attributed to Tim Miller, reproduced verbatim across dozens of studio sites. It has been on the Ashtanga Yoga Center's own site, unsigned, since at least 1 June 2002, where the Internet Archive caught it with a live moon calendar for that year attached. No earlier dated reproduction exists anywhere I could find, in print or online.

So the canonical text of the explanation — the one paragraph reproduced on hundreds of studio sites, usually with no source at all — is a web page that has been sitting on one American teacher's site for twenty-four years, carrying no byline in its own text, restated until it hardened into doctrine. The observance is Guruji's. This particular wording of the reason is not.

It is worth reading what that page actually argues, because almost nobody quotes this part:

Like all things of a watery nature (human beings are about 70% water), we are affected by the phases of the moon… Both sun and moon exert a gravitational pull on the earth.

That is the whole mechanism, stated plainly, and it is not true. The moon's tidal force across your body is about a billionth of a gram — a mosquito on your arm beats it two thousand times over. The document that gave the tradition its reason gave it a physics that does not work.

What Jois himself is reported to have said

The reason students report from him is not the prāṇa/apāna paragraph, and it is not nothing. It is astrological and it is about the body: that when earth, sun and moon line up, a particular conjunction of nakṣatras — the lunar mansions of jyotiṣa — makes injury likelier and slower to heal, and that the energy of those days is not the energy of ordinary practice. Eddie Stern, who had it directly, relays both that claim and a second one — that a teacher who introduces new material on a moon day will find his own knowledge declining.

That is in character. "Jois" is itself a South Indian rendering of jyotiṣa. Astrology was the family trade, and he cast charts.

This reaches us through students recounting what they heard, which is how most of this lineage reaches us. It is testimony, not text — but testimony from many independent people who were there, saying the same thing, is real evidence and should be weighed as such. What it will not do is licence the specific physiology of the web-page version, which nobody attributes to him.

Where the calendar came from is a different question

In 2013 Eddie Stern — who co-edited Guruji and knew the household as well as any outsider — wrote a letter explaining moon days, and his account has nothing to do with energy.

Jois taught at the Maharaja's Sanskrit College in Mysore from 1937 to 1973. That college closed each month on amāvāsyā and pūrṇimā, and on the days either side. Not for yogic reasons. Its Brahmin teachers and students had ritual obligations on those tithis — pitṛ tarpaṇa, the offerings to the ancestors, which fall on the new moon, and ritual bathing after.

The college shut. So the yoga shāla shut. Jois kept the rhythm of his working life for thirty-six years and carried it forward into his own teaching, and the rest of us inherited a Sanskrit college's holiday calendar and went looking for a reason.

Stern is careful to mark the two claims he relays as traditional assertions he could not himself verify. That care is worth copying — in both directions. It is as much an overreach to say Jois did not really mean anything by moon days as it is to publish the web-page physics as his teaching.

Nobody else does this

Moon days are not a feature of yoga. They are a feature of this lineage.

Krishnamacharya taught Jois and he taught Iyengar, and the Iyengar world does not observe moon days. Neither does the Sivananda line, nor Scaravelli's. Students of Krishnamacharya's broader circle practised straight through every phase, because it was never part of what he gave them. The practice descends through Pattabhi Jois specifically, and through the Mysore timetable he kept.

The moon in the texts is inside the body

There is a temptation, when the sourcing gets thin, to reach past Jois into the haṭha canon and say the old books were talking about this all along. They were not, and the reason matters.

The haṭha texts have an elaborate moon. It is at the palate. From it drips amṛta, the nectar, and a sun at the navel consumes it, and that consumption is why the body ages.

That is Haṭha Yoga Pradīpikā 3.77, and the verses after it teach viparīta karaṇī — turn the body over, and the sun is now above and the moon below, and the nectar is no longer consumed. Inversion as a way of not spending yourself.

This is a moon you carry. It has a location in the body, it is paired with a sun, and the practice is done to it rather than in response to it. Nowhere in that material is there an instruction to stop practising when the moon in the sky is full. Reading the calendrical observance back into these verses is a category error, and a common one.

Even haṭha itself will not settle down. Brahmānanda's Jyotsnā commentary glosses ha as sun and ṭha as moon; the Yogabīja reverses it; a third reading takes the word as plain force and no sun or moon at all. Two incompatible etymologies inside the tradition, on the tradition's own central word.

So should we practise?

Here is the honest position.

Guruji kept these days and taught that they mattered for energy — that is attested by everyone who was there, and it is the part of this that is solid. The written reason you were given, the one about prāṇa at the top of the inhalation, is not his; nobody can source that paragraph to him. The calendar itself traces to a Brahmin college's ritual days, kept for thirty-six years by a teacher who worked inside it. The physics of the moon's pull on your body rules out the mechanism people reach for — see the pull, where the number is a billion times smaller than a gram. And the one real lunar signal in human physiology is in sleep, not in tissue, and is smaller and stranger than the folklore.

None of that is an argument for practising on moon days.

A rest day twice a month, fixed in advance, that nobody has to justify and nobody can negotiate, is a good thing to have in a practice that otherwise runs six mornings a week and rewards not stopping. It arrives whether or not you are tired, which is the point — you do not get to decide you have earned it. It puts every student in a room on the same schedule, which is how a shāla stays a shāla instead of a gym. And it ties the practice to something that is not the practice: a body in the sky, visible from anywhere, on a rhythm nobody set.

Those are real reasons. They do not need prāṇa and apāna, and they survive finding out that the traditional explanation cannot be traced.

What I would not do is teach the web page as though it were Guruji. Say the practice is a lineage observance that he kept and meant — which is true, and sufficient. Say, if asked, that the reason he gave was astrological and about injury, and reached us through his students rather than in writing. Say that the paragraph on the internet is somebody else's, and that its physics does not hold. All of that is honest. Reproducing an unsigned web page as his teaching is not — and neither is the opposite error of implying he was indifferent to a day he never once let anyone practise on.

And keep your shāla's list. The dates that close your room are the dates that close your room; the calculator here exists to show you why two rooms disagree, not to overrule either.

What I tell students

We take the day off. Guruji took the day off, his teacher's institution took the day off, and the shāla in Mysore still does — this is a lineage observance and we keep it. What I am not going to do is hand you the paragraph off the internet about your prāṇa being high at the full moon, because nobody can show you where that came from, and the physics in it does not work. What Guruji himself said, as far as anyone who was there reports it, was simpler: the energy of these days is different, injuries come easier, do not push.

Here is what I will tell you. The rhythm is older than the explanation, and it is not nothing to keep a day that arrives on its own schedule rather than yours. Six mornings a week, the practice asks you to show up whether or not you feel like it. Twice a month it asks you to stop on the same terms — whether or not you feel like it. Most of us are much better at the first instruction than the second.

The day is also the one thing in the schedule that nobody in the room decided. It comes from the sky. There is something worth keeping in an observance that is not about how anyone is feeling, cannot be earned, and cannot be argued with.

If you practise anyway on a moon day, nothing will happen to you. If you take the day, you will have taken a day. Take the day.

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