tune by Shaun Davey, words collected in Barra, Western Isles, Scotland and first published in Carmina Gadelica circa 1900.
The lyrics seem to be a fusion of an older sun-worshipping tradition with Christianity.

recorded on the Shaun Davey album "The Pilgrim" with singer Rita Connolly and on Kathleen Mac Innes cd "Cille Bhríde" KMAC00. You can also find recordings of performances by Kathleen Mac Innes and by Rita Connolly on youtube.

A' GHRIAN

Fàilte ort féin, a ghrian nan tràth,                            
'S tu siubhal àrd nan speur,
Do cheumaibh treun air sgèith nan àrd, . 
'S tu màthair àigh nan reul.

Thu laighe sios an cuan na dìth, 
Gun dìobhail is gun sgath, 
Thu 'g éirigh suas air stuagh na sìth, 
Mar rioghainn òg fo bhlàth.                                                    
                                                                              
Tha mise an dòchas 'na thràth, ,
Nach cuir Dia mòr nan àgh, 
As domhsa solas nan gràs 
Mar tha thusa dha m'fhàgail a-nochd.

singable translation to Irish Gaelic by Risteard Mac Gabhann:
AN GHRIAN

Fáilte romhat, a ghrian na ráithí, 
's tú ag siúl in ard na spéire, 
Do chéim go tréan ar sciath na n-ard,
Is tú máthair ard na réalt. 

Tú 'do luí i gcuan na díth’,
Gan díobháil is gan scáth,,
Tú ag éirí suas ar stua na síth’,
Mar ríon óg faoi bhláth.                                                   
                                                                              
Mise ag súil in am tráth,
Nach gcuirfidh Dia mór na ndúl,
As domsa solas na ngrás
Mar 'tá tusa dom’ fhágáil anocht.

translation to English (by ___?)
THE SUN

Hail to thee, thou sun of the seasons,                           
As you stride the heights of the sky,  
Stepping firm on heaven's wing,
You are the noble mother of the stars.

Lying low in the harmful ocean,
Unharmed and without fear,
Rising again on the arch of peace, 
Like a queen in the bloom of youth.                                                   
                                                                              
I hope that in the course of time
That the great and gracious God,
Will not extinguish for me the light of graces,
Just as you are leaving me this night.