Just in time for the season! Dream a Dream by Charlotte Church, featuring Billy Gilman. Simply beautiful, if you haven't heard it, click here now!
I'm not exactly sure how it has a Christmas message, but it was in Charlotte's Christmas album :D
It reminds me of Cleris because of the 'finding Elysium' part, aka finding Paradise, aka the Promised Land :) Cloud of course, is the 'lonely shadow', Aerith is the 'light'. But enough babbling, here are all of the lyrics:

Dream a Dream
Charlotte Church feat. Billy Gilman
When the night is still,
And the sea is calm,
Lonely shadow
You fall upon me
Lay by my side,
Fear not tonight,
Lonely shadow
You'll find
A new light

Dream a dream
And see through
Angel's eyes
A place where
We can fly away

Ride with me
Upon a shining star,
Above the moonlit sky
We will find elysium

Hear the nightingale
Sing a lullaby
Lonely shadows
You'll find a new light

Dawn will be kind,
All will be bright,
Lonely shadow
Rise from
The darkness

Dream a dream
And see through
Angel's eyes
A place where
We can fly away

Ride with me
Upon a shining star,
Above the moonlit sky,
Once more

Dream a dream
And see through
Angel's eyes
A place where
We can fly away

Dream a dream
And see through
Angel's eyes
A place where
We can fly away

Elysium
Elysium

It's such a beautiful song, Kusari :o
I agree with you, it's extremely Clerisy. I can really see Aerith saying those words to Cloud.

Terrific find, love the lyrics.
I see potential for a new Cleris FMV ^^