We know the tenets and some interpretations
The tenets of the litany are all written down in the sourcebooks. Or rather, their English translation is. What each tenet means is a huge set of precedent and interpretation by the tribes, and can be found only in parts in the tribe books. The 13 core tenets are simple, but what each tenet actually means, is, again, up to discussion and interpretation. And that is done extensively in each tribe book. Yes, each of the tribes interprets the rules differently. And weighs them differently. Like, check out how different each tribe stands to something as simple as love and that is just the tip of the iceberg. And that is just looking at one of the tenets under a very narrow focus (Garou shall not mate with Garou), to which each tribe has at times opposing opinions.
And each tribe and camp in each tribe has its own sub-rules and tenets of its own! For example, the Hand of Tyr has a rule that demands them to hunt down the west scum of society that preys on the weakest of society but bans harming innocents 1. On the other hand, Harbinger Silent Striders are constantly on the move searching for signs of the Wyrm because that's their internal mandate.
Then, also note that all we know about the litany is in character speech. All those tidbits and explanations? That is what one Garou tells a young one or someone of a different tribe to make it easier for them to understand their society. But they don't tell us the actual litany - just their interpretation.
So, many words, what does that mean? Well, a lot of what the litany is, is how the local lead-garou interpret it. That means the council made from the Caern Elders determine what is and what isn't a breach of the Litany, and they bow down to the regional councils and the Garou Nation.
In a pack, it is up to the Philodox to judge, and the Alpha to make sure it is held up. And of course, packs also follow a totem, that has rules and tenets the pack has to follow, adding those to the personal litany...
In the end, the basic litany all tribes seem to agree on is just the basic list of the 13 tenets, which can be better described as chapter headers for the actual parts of the litany. We also only interpolate from what each tribe tells us about their interpretation of the litany and guess what might be in there, but we are never actually told: Besides the Tenets there is not a single actual quote from the litany in any of the Tribe books compiled under the Litany of the Tribes series. But they are, as already mentioned, discussions of each of the tribes with someone that is not (yet) engrained in the culture of that tribe. But In the end, reciting the whole litany is claimed to take hours...
The Silver Record
The best match for even a sliver of Litany beyond those elaborations might be the Silver Record, thick and full of Garou lore and tales. However even that does not contain the litany, and that should have been the best place to put it. But at times it has a little glimpse of what might be in the litany, as it is written explicitly as some sort of guide to the litany:
the Silver Record is [...] a combination of history book, behavior guide, family album and gospel 2.
And even there, the book itself says, that the glyphs that are the actual Silver Record exist in variations and can be interpreted differently 3. So even that book is just one interpretation, the one of the young Philodox Keeper-of-the-Record Wyrm-Takes-Last. His Silver Record has about 70 pages of content to be told. 70 pages take about 1.9 hours to read silently, so that part alone is up to 3-6 hours to be read aloud - as you read much faster for yourself than out loud.
So we only have the chapter headers and 2nd hand interpretations of the litany. The closest we get with the Silver Records might be at times described as the Appendix to the Litany itself.
Changing Ways, the closest thing to a W20 players guide we got, has a rare insight into a single tenet, devoting an entire chapter to the First Law of the Litany, directly comparing the first law of the litany with the second amendment:
At face value, it’s simple, right? Garou Shall Not Mate With Garou. The problem here is the word “mate.” It causes as much interpretational trouble as that damn comma in the Second Amendment of the American constitution. [...] True, this is a translation from the Garou tongue, but it tends to crop up in all translations. [...] The Litany was created in primordial times, and I believe that those who wrote it had a simpler, less “lawyery” way to look at things, which is why this law is now up for interpretation. Some tribes — the Fianna, Red Talons, and Wendigo chief among them — go in for a very strict interpretation [...] 4.
But the very same book also points out later, when displaying typical Philodox-Lupus, that the litany itself might be nothing more but the tenets, and a pack portrait again tells us, that the litany is at least in part a huge canon of precedent and interpretations:
The Litany is simple enough to learn and understand. Some things Garou do, and some things Garou don’t do. 5
Steven Tilts-at-Windmills (homid Fianna Philodox) spends his days as a poli-sci undergraduate at Ohio State University, and his nights delving into study of the Litany. He has an in-credibly gifted mind for precedent and interpretation... 6
- TB: Get of Fenris p.27
- The Silver Record p.5
- The Silver Record pp.6
- Changing Ways p. 57
- Changing Ways p. 91
- Changing Ways p. 122