Orthodoxy in Christianity is the holding to the oldest beliefs. It is of course impossible for the religion not to evolve at all as new questions and there answer have to addressed. The "Orthodox" version is often considered to be the least evolved sect of a religion. Does the concept of Orthodox apply in Buddhism?
Well, Theravada is often argued to hew most closely to the original teachings of the Buddha. See, e.g. "Two Main Schools of Buddhism" for a very brief overview of this.
As I understand it, this has much to do with the fact that Theravada is the oldest of the extant Buddhist schools of thought, predating Mahayana by a few centuries. Theravada practice is also more localized to geographic regions nearer the birthplace of Buddhism (that is, Sri Lanka and Southeast Asia), and never strayed far from it; this is thought to have contributed to the "orthodoxy" of the school - it mixed less with other intellectual and spiritual traditions.
Additionally, Theravada Buddhists draw primarily on the Pali Canon (the Tripitaka), whereas Mahayana Buddhists draw primarily on Chinese sources. These Chinese sources are relatively more distant from the original teachings of the Buddha in terms of both time and language. As a byproduct of this, the Pali texts are often more "authentic".1
That said, the term "Orthodox" has no specific meaning in the context of Buddhism, i.e. there is no such school as "Orthodox Buddhism". There are only lowercase-o "orthodox schools of Buddhism", and what counts as "orthodox" will probably differ depending on who you ask. I should add that pre-sectarian Buddhism is almost definitionally the most "orthodox" school of Buddhist thought. The only problem is that, well, it doesn't exist anymore.
1 See, e.g. Rupert Gethin's The Foundations of Buddhism, p. 44: "it is likely that [it] is generally the case [...] that the traditions [the Pali recension] preserves are [...] the oldest and most authentic available to us" (elisions/etc because the original sentence was inverted)
There is no Orthodox Buddhism, there is Traditional Buddhism. Most modern traditional branches of Buddhism with monkery, root in some or other ancient school. Theravada is not more Orthodox or ancient than most other traditional schools.
Orthodox Buddhism would be what we call Early Buddhism, which does not exist any more, as a tradition or school or sect. Early Buddhism split into the Mahasamgika school and the Sthavira school.
The modern Theravada tradition, is probably the closest modern school to Early Buddhism, in terms of its doctrines. Theravada is based on the Sri Lankan Mahavihara school, which descended from the South Indian Tamraparniya branch of the Vibhajyavada school, which descended from the Sthavira school.
In this blog post, Bhikkhu Sujato wrote:
The term sthavira (meaning ‘elder’) is the Sanskrit version of the term better known today in its Pali version thera, as in Theravāda, the ‘Teaching of the Elders’. The original Sthaviras, however, are by no means identical with the modern school called Theravāda. Rather, the Sthaviras are the ancestor of a group of related schools, one of which is the Theravāda.
To me, the most orthodox teachings of Buddhism are found in the Theravada Sutta Pitaka and the Mahayana Agamas, which are essentially the same thing.
Personally, I don't consider the Theravada Abhidhamma and the later Mahayana Sutras (like the Lotus Sutra or Heart Sutra) to be orthodox.
James Jenkins, those interested,
it's a sign of the Dhamma-Vinaya, the Buddhas teachings, to be very orthodox and it's because his good following disciples stayed by what was taught by him as much as they could remember and recollect, that his "(re)-legion" could be brought till this days and is still alive to be used.
What ever "unorthodox" approaches, often simply copies, are traced, can, for the most, be seen as not of what the Buddha taught and advice, yet he gave a lot of advice to proof such seriously without either to reject or take on it at first place, if unusual practices and teachings are approached and one of this sets of tools to prove is called Great Standards, also found under the link above, among other tools to verify the "orthodoxy" and validity of sayings and usual, mostly alien to the Theras (Elders of the monastic community).
While the practice of lay-followers may change over time, which is surely often also followed by certain disciples and particular communities of monks, of course always lead by certain improper desires, the ways the so called "Savaka Sangha" (community of good following disciples of Bhikkhus), the way of the Noble Ones didn't really changed, is still, even if hard to trace and find, alive although decaying naturally. Once the (Re)-legion goes astray, there is no much benefit for it, better it could not contribute much for benefit in the world, which is also a reason why this (re)legion would not adapt common desires simply for the sake of existing on or for maintaining ways of merely for the use of just livelihood and entertaining.
Once the "Religion" is or appears no more orthodox it will be no more maintaining a monastic Sangha which is a huge and unexcelled field of merits.
The essay and collection of That the True Dhamma Might Last a Long Time: Readings Selected by King Asoka may give also some impressions of the Dhamma-Vinayas ("Budddhisms") orthodoxy, which is actually, although claimed otherwise, even since the Mahaparinibbana of the Buddha, most compassionate this upholding of orthodoxy.
Now at that time, one Subhadda, who had renounced only in his old age, was seated in the assembly. And he addressed the bhikkhus, saying: "Enough, friends! Do not grieve, do not lament! We are well rid of that great ascetic. Too long, friends, have we been oppressed by his saying: 'This is fitting for you; that is not fitting for you.' Now we shall be able to do as we wish, and what we do not wish, that we shall not do."
But the Venerable Maha Kassapa addressed the bhikkhus, saying: "Enough friends! Do not grieve, do not lament! For has not the Blessed One declared that with all that is dear and beloved there must be change, separation, and severance? Of that which is born, come into being, compounded, and subject to decay, how can one say: 'May it not come to dissolution!'?"
What ever one nourishes, inwardly, outwardly, that will grow and resist for the individual as well as the opposite. It's seldom, very seldom that one gives into Upasnissaya of the Noble Ones, but having done and do so, one does not need to worry to come not near and sooner or later access the Orthodoxy that leads not only to heavens but to final release form all stress and suffering. Good and bad choices are individual ones, yours, which no one could force.
James Jenkins stated in his question:
"It is of course impossible for the religion not to evolve at all as new questions and there answer have to addressed.", actually it is, was done by the Sublime Buddha, to release a timeless path and teaching, ever-trace and usable for those ready to be tamed.
(Note that this is not given for trade, exchange, stacks or entertainments binding one in this world but as means for an exit from this wheel)
There's no such thing as orthodox in Buddhism. But when translating the real meanings of Buddha is changed. And also in Pali canon it's mentioned that, buddha has mentioned dhamma should not be translated to Sanskrit, its believe that reason for saying that is tge true meaning of words are changed when translating. Eg: Lokaya = World (Loka Sutta), And when we add ‘a' infront, which is Aloka it means Light. So when you uproot Loka (world=Five Aggregates of Clinging) you will see the Aloka = Light which is Nivana or Enlightment. So the meanings of these suttas are built in to words it self (This is Pali and Sinhalese language). Apart from that ther's no any thing call orthodox.
That's a broad question, I think the answer is "yes and no", so I'll try several small answers.
The word "Orthodox" has several meanings:
- The true or correct teaching, the Right doctrine
- By extension, and with reverence to the founder of the religion, the earliest or original doctrine
- A conformist practice, a practitioner who tries to conform to the orthodoxy
- A school or church which is named "orthodox"
Maybe everyone -- Buddhist or not -- wants to seek or have, or will claim to have, #1 ... even if their version may appear to contradict #2, #3, and/or #4.
According to Wikipedia, one of the current schools is called "Theravada" (the Way of the Elder Monks) which seems to me (though I may be wrong) to imply "original" or "orthodox".
It says the name derives from "Sthavira" (which I find a bit strange because now there's bias against Sanskrit in favour of Pali, but that's a different topic).
This Origin implies that schools used to argue (and split) over who was orthodox and who was schismatic.
I've seen a modern user (on this site) write that this kind of topic is of interest to scholars and historians, but that "to us, it's just Buddhism".
What is in a name, anyway?
There are political parties named "Conservative" or "Socialist" or "Republican", but that's just the name.
There's little difference IMO between the Orthodox and Catholic churches -- mostly a different set of bishops and a distinct geography, i.e. Eastern versus Roman.
So with such large churches having such slight differences, and a schism which didn't happen until 1054 AD, you might feel safe in thinking that at least one of these churches is "orthodox". But then the protestant reformation happens -- people say, "The church is teaching and practising in ways which Jesus would never have agreed to".
And so you get people like John Fox who don't support the Established church but claim to be (and seen by some to be) closer to the truth (maybe closer to the "spirit" of the doctrine) than is taught from scriptures.
Perhaps there were already differences, between the "Buddhism" that was taught and practised when Gautama Buddha was teaching (in maybe 450 BCE), and "Buddhism" when it became the State religion in about 250 BCE.
Buddhist schools today (and historically) put some importance on "lineage" -- who taught your teacher (etc.)?
Many people will see that (i.e. a living teacher) as more important than the history-of-literature considerations
There's also sometimes a question of whether someone has been authorised (by their own teacher or school) to teach.
So that's a bit of both: i.e. traceable historically, and modern.
Everyone agrees that the Buddha's doctrine, the Buddha's words -- Buddhavacana -- are important and good.
So people sometimes disagree about whether something should rightly be considered or classified as "buddhavacana", and have different definitions.
The official or canonical answer to that fact are that "Buddhist councils" were convened and they decided what's what, and we accept that.
Even so there are scholars and practitioners who think that on at least a few points it's likely that the current doctrine isn't or can't have been "original" (see this answer for one example).
Part of the monastic code is that you shouldn't cause a schism in the sangha (which I guess inclines toward orthodoxy).
There's some emphasis in the doctrine though about what "knowing for yourself to be true", so it's not maybe meant to be a slavish adherence to nonsense -- not "conformism above all else".
The above all seems quite pedantic. I think there are entire countries which get on without bothering which such trifles -- for example:
Followers in Vietnam practice differing traditions without any problem or sense of contradiction. Few Vietnamese Buddhists would identify themselves as a particular kind of Buddhism, as a Christian might identify him or herself by a denomination, for example.
The overall doctrinal position of Vietnamese Buddhism is the inclusive system of Tiantai, with the higher metaphysics informed by the Huayan school (Vietnamese: Hoa Nghiêm); however, the orientation of Vietnamese Buddhism is syncretic without making such distinctions. Therefore, modern practice of Vietnamese Buddhism can be very eclectic, including elements from Thiền (Chan Buddhism), Thiên Thai (Tiantai), Tịnh độ Pure Land Buddhism, and popular practices from Vajrayana.
Perhaps there are some differences but they're not a big deal, not worth fussing about. Or maybe it can be said that the schools have a lot in common.
It may be that questions of "orthodoxy" are a type of conceit -- "I am orthodox, we are orthodox, you are not orthodox".
I say conceit because, to me, "orthodox" implies a comparison (i.e. compared with unorthodox or non-orthodox), and this answer implies that comparisons derive from conceit.
We are also warned that conceit and so on, maybe attachment to views, lead to sectarian arguments.
In practice I think that, for some people, their view of Buddhism overlaps with nationalism ("our country has the best, perhaps the most orthodox, form of Buddhism") or sense of national identity.
I guess that's human, as far as it goes, unless it becomes inhumane.
The vinaya (the monastic code) changes little or not at all. There's a story associated with one of the suttas, that at parinibbana the Buddha said he'd allow the monks to change any minor monastic rules, and they never did because they'd never agree on which rules were only "minor".
There are different versions of the vinaya from country to country, but that's an example of an orthodoxy.
In practice there are "monks" who don't try to follow the vinaya in detail.
I guess conformance is sometimes judged by an abbot and/or community of monasteries.