We have taken this not too strict: Sindarin would be hard to use if we had, because the Ainulindalë is of course the description of the Valar, for which Quenya is much mure suited.
Therefore, I chose to write from a Middle-Earth perspective when describing a Vala or Maia - in this case it is the Maia Melian, Tinúviel's mother who went back to Valinor after the ruin of Doriath and the death of King Elu Thingol. Lúthien Tinúviel had come back to Middle Earth with Beren to lead a second but mortal life together, and one of the sorrows that followed from that choice was the severing between her and Melian until beyond the circles of the world.
I imagined Tinúviel singing to the moon one night in Tol Galen, as once she did before in Doriath. This time she asks the moon whether it looks upon all the lands that she has seen, and maybe also on Valinor, to see her mother, whom she misses.
Ai Ithil! Or chîth hwiniol
vi Menel i thamas haered
bo vâd uial athradol
man hae pelil ennas cened?
Pelil cened an Neldoreth?
Lilthassen nef i hîr glavrol ...
Pelil cened na Doriath,
i arnad i Elu Thingol?
Pelil cened Beleriand?
O Hithlum ring na Forodwaith?
Na nan galen, Ossiriand:
pan i ennor in Elenwaith?
A cenil aen, Ithil sadar,
athan aear, ned Annûn fain?
I vardor idh rodyn aglar
a dhôr edhil telyg ammain?
Ennas dhôr hen, mellon anann,
vi Lórien, gelaidh olthar
vi 'wath ferin ah mallorn brann
lastol i merilin linnar?
Ae linnar aen, si hain linnar
na Melian, i rîn aglar?
Udul he ad na Valimar
ab Thingol gwannas i amar.
Min gelaidh ah lyth olthiel
merilin linnathar ammain,
or nen Lorellin miriel:
úlastathon, a Ithil vain.
A! Oh moon of silver light
high up in the sky tonight
gazing upon of from above
how far can you see from there?
Can you see the forest of Neldoreth
where once I danced to a pipe unseen
can you see all of Doriath
where Elu Thingol once was king?
Can you see all of Beleriand?
from cold Hithlum to green Ossiriand?
from West to East, from North to South
do your eyes encompass all that?
And can you see, Oh trusty Moon
across the Sea, into the West?
The land to where my people go
The land in which the deathless dwell?
Somewhere there, Oh shining Moon,
there lies the wood of Lórien
where in the shade of twilight trees
the nightingales still sing?
And would perchance they sing today
to honor Melian the fair?
Returned she has to Lórien
when Elu left her side
Amidst the trees and Irmo's bloom
across Lorellin ever-sweet
Her singing sound forever there
but not to me, oh Moon so fair.
The drawing that you made to accompany it is beautiful as well.