To me it sounded a bit like "To Be A Pilgrim" - John Bunyan's hymn. But that music was written by Vaughan Williams, based on an English folk song. Could the French by poaching English folk songs as well? :-)) * In fact, the organ melody from Saint Saens' 3rd Symphony is not a hymn tune, though Saint-Saens may well have taken a phrase here or there from well-known hymns, and reworked it to make it completely original. The melody was popularised in 1977 as the song "If I Had Words" by Yvonne Keeley and Scott Fitzgerald. The film clip was set in a church, complete with congregation waving their arms, so it may have given the impression it was based on a hymn tune. The only connection to hymns was the use of an organ.
A composition for an organ that incorporates a hymn tune is known as a chorale prelude.
hubert parry, if you are referring to the Blake hymn
Cantata I believe.
A mighty fortress is our God
It is not clear when the hymn tune "Adeste Fidles" was written. The thought it is that it may have been written in the 13th century by John Francis Wade.
The hymn that has this tune is called, "Come, Christians, Join to Sing." The lyrics were written by Scottish minister Christian Henry Bateman in 1843.
Mozart Symphony 40
Spyros Samras composed the olympic hymn.
Could be anything depending where in the world you worship but in the Methodist Hymn and Tune Book: official hymn book of the Methodist Church‎, Pleasant are Thy Courts Above is hymn number 230