Be he foe or friend, be he foul or clean,
brood of Morgoth 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. 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!

>>211790224 (OP)
I love Silmarillion so much. Read it three times back when I was 17. Shame that it doesn't actually contain the Oath, that is from Tolkien's notes in Book of Lost Tales.

>>211790293
There are also 3 poetic versions in the Lays of Belereiand.
LoB also references fauns, this is why faunposters have been quiet last few years.