It's a beautiful song, but you misread the title, and they have it partially wrong on that site anyway:

Coinnle an Linbh Íosa [the last word begins with a capital "I", with an accent on it [Alt 0205 on a pc keyboard]
The [Candles/Lights] of the [Child/Boy] Jesus

I found the last verse online (it starts at 1:17 on the You Tube version -- what comes later, near the end, is a repetition of the first verse). Some of the wording, such as trís and sroisfidh, is dialectical. I'm not sure what sí means in the third line ("spirit" seems odd there), so that's probably dialectical, too.

Seo Féile an Rí Bhig, seo Féile 'bheidh buan
A Sheas trís na haoiseann' 's go lá lom an Luain
Guím Nollaig dheas aoibhinn gach sí agus suan
Ar chairde mo chroíse go sroisfidh siad Cuan

This is the festival of the Little King. a festival that will last
It will last through the ages until judgment day.
I pray for a nice pleasant Christmas, every ___ and rest
To the friends of my heart - May they reach harbor.

There's CD available online which apparently has has all of the words (and 20 other Christmas songs), but it's pricy:
http://www.theschooldepot.ie/product_p/sch0026.htm