"For this kind of oath yes; you just specify that this is what they swore and not any oath you've ever taken. That'd be safe even if you had already awakened, and you can always insert "they said" every other line to be careful.

If saying the words triggers your kind of oath regardless, can you tell me every second word? And then the other half and I can put it together."

"Inserting 'they said' is safe by our rules, if it's safe by yours. 

They said: "Be he foe or friend, be he foul or clean,

brood of Moringotto or bright Vala,

Elda or Maia or Aftercomer,

Man yet unborn upon Middle-earth,

neither law, nor love, nor league of swords,

dread nor danger, not Doom itself,

shall defend him from Fëanor, and Fëanor’s kin,

whoso hideth or hoardeth, or in hand taketh,

finding keepeth or afar casteth

a Silmaril.'

They said, 

'This swear we all:

death we will deal him ere Day’s ending,

woe unto world’s end! Our word hear thou,

Eru Allfather! To the everlasting

Darkness doom us if our deed faileth.

On the holy mountain hear in witness

and our vow remember, Manwë and Varda!’"

"Those idiots."

"I know," he growls. "I know."

"Practitioners' oaths are very literal. If I were to swear that none shall go hungry whom my hand can feed, it would count as fulfilling the oath if I make sure never to have the chance to feed any hungry people. Is the same true of this? If so, they'd be doomed to whatever the Everlasting Darkness is if someone else killed the person they were after and then gave them the Silmaril!"

"I - intent matters, if that interpretation didn't occur to them I don't think they'd be stuck with it. Normal people just never ever swear anything, there's so much risk, let alone doom you and your kin to the Everlasting Darkness for a promise -"

"Okay, so it's marginally less stupidly dangerous than it would be if a practitioner swore that, except that it doesn't even come with the positive side of oaths-"

"And if they became practitioners, and affirmed that they meant it, it'd be stupidly dangerous your way."

"Maybe. Oaths being literal does work both ways. They could say that when they swore to follow the old oath they meant the same content as the old oath, not the same words. If they went and swore it again word for word they'd be stuck.

What's a Silmaril, anyway, and who do they have to kill?"

"The Silmarils are magic jewels that my uncle made. They contain the unsullied divine light of Arda and can do all sorts of things, but none which justify this. And they have to kill the Vala who's besieging the continent."

"Oh, if it's only him that's the least bad answer available. If I were in the Enemy's position and had no ethics whatsoever, I might pass it to people on a rotation and send people who have hoarded Silmarils off where the oath-takers can never find them. And make sure they knew it, of course."

"The Enemy has not yet demonstrated that much creativity. The lack of ethics is consistent with things he has done."

"I guessed that part.

If intent matters, I'm guessing they didn't mean to include themselves as people who keep a Silmaril? Otherwise the Enemy could just send them one, and- ugh. Yes, let's keep magic very far away from these people."

"No. No, they didn't mean to include themselves. You know, I really appreciate getting to talk to someone who feels the full magnitude of how monumentally stupid this was."

"Where I come from this is an obvious mistake. Practitioner families raise their kids from a young age to make sure they never do this exact thing. I assumed it was a cultural difference, since non-practitioners don't, but your entire species has this and they did it anyway. Do other people just not notice how big of a deal this is?"

"So I told you that my uncle was the King of our people and that a succession dispute was the immediate cause of us being stranded here? Well, he was popular, he was gifted, everyone was happy to follow him as King, and then he did this and they asked my father to take the job instead. Around two thirds of all our people. People know what a big deal it is."

"Then it sounds like you wouldn't lack for people who know just how stupid Fëanáro was being."

"We don't. We just don't talk about it, and it's old news now.

And his children are - well - actually it's a bit of a fucking mess but - 

- if there's any way at all for them to not be doomed to the everlasting darkness I don't think I want them to be doomed to the everlasting darkness."

"A ringing endorsement," Irissë says drily. "Is this a situation where you need full information? Because if so, Findekáno -"

"I'm not sure what I'd need full information for. Since intent is binding here, finding what would otherwise count as a catch in their oath wouldn't help. And presumably we all agree on goals of Moringotto being beaten and the Silmarils returned to the idiots who will then not be forced to kill people.
If there's information that it would cost to tell me, it might not be worth it."

"That makes sense," he says firmly. "All right. We will not lie, will not even mislead if we can avoid it, and will never ever make an Oath never ever, and we can commit that we aren't having children so we don't have to worry about passing our mistakes on to them."

"Right," Irissë says firmly.

"Those are all good policies, but you probably shouldn't repeat that after awakening. Even with oaths, swearing that you've been completely honest can sometimes help negotiate with untrustworthy people."

"I was not planning to, immediately after awakening, swear not to swear Oaths, no." He smiles. 

"All right. Ritual.

I've got the words written out, in my language and in the older language I don't speak that you'll be saying them in. We don't share an alphabet, but I could send you the syllables through osanwë. The content translates to pledging truthfulness in exchange for joining the world of practitioners. The ritual is about introducing yourself to the spirits; you'll get marked as people to listen to.

A lot of it, especially toward the end, isn't scripted. The objects we've set up will move around and show themselves, and you say whatever it makes you think of. Normally this is one-word responses except for the personal token, when you say who you are and who or what you're doing this for. But if you want to use more words, that's entirely allowed.

Um, it does have to be done naked. I don't know what your nudity taboos are like, but the clothes-wearing people can survive away from the heat source for a little bit.

Afterward, your vision will look different. I can't tell you how because it's different for everyone, but you'll be seeing magic and spirits. You can turn this on and off, and should leave it off except when needed."

"We don't have a nudity taboo; do we have to unbraid our hair?"

"Is that the equivalent thing here? Probably not; if it works it's because it's doing the same thing as it would in my world and it's just clothes that matter there. But it wouldn't hurt, magically at least."