Although I disavowed my Christianity by converting to Judaism, I was in church choirs for years (OK, I still am) and I retain a real fondness for hymns, which are the folk music of popular Christianity. They often are, or become, a form of vernacular poetry, and many of them are really powerful:
'Tis by thy strength the mountains stand,
God of eternal power.
The seas grow calm at Thy command,
The tempests cease to roar.
The thirsty ridges drink their fill,
And ranks of corn appear.
Thy ways abound in blessings still,
Thy goodness crowns the year.
The above is by Isaac Watts, the "Father of English Hymnody," and was set to the vigorous fuging tune Rainbow by the eighteenth-century Massachusetts composer Timothy Swan (MIDI links in the Wikipedia article). I love hymns not least for the way they reflect their time and the way belief was shaped in different periods, from the stark puritanism of Watts' Broad is the road that leads to death to the stolid but strangely ecstatic Welsh Methodism of Guide me, o thou great Jehovah to the nearly Transcendentalist mysticism of Dear Lord and Father of mankind.
It's not just the words, I think; it's also the music: from the stout irregular Geneva Psalter meter of Comfort, comfort ye my people to the sentimental Victorian expressivity of The day thou gavest, Lord, is ended to the Georgian modernism of For All the Saints, whose tune "Sine Nomine" is by Ralph Vaughan Williams. There's even one Christian hymn borrowed straight from a 15th century Jewish source: The God of Abraham Praise is simply an English paraphrase of the Yigdal.
Once, when I was in college, a member of the alto section in my choir was taking a geology course which was giving her terrible trouble. One Sunday the closing hymn was the abovementioned "Dear Lord and Father of Mankind," which is based on a poem by John Greenleaf Whittier, called "The Brewing of Soma." The poem comes out of late nineteenth-century discovery by Westerners of the religious literature of India and East Asia: in this case Whittier is imagining the Vedic priests drinking the hallucinogenic soma to induce religious ecstasy. Whittier was a Quaker and an abolitionist, and thought that excessive ritual in Christian worship was akin to the drinking of soma: an experience that obscured rather than made straight the way to God. The next-to-last verse of the hymn is as follows:
Drop Thy still dews of quietness,
Till all our strivings cease;
Take from our souls the strain and stress,
And let our ordered lives confess
The beauty of Thy peace.
The alto confessed that she nearly burst into tears at singing this, since she had an exam on Monday which involved some fiendish equations related to strain and stress in plate tectonics. I'm not sure that Whittier would have foreseen this interpretation; but the last verse goes:
Breathe through the heats of our desire
Thy coolness and Thy balm;
Let sense be dumb, let flesh retire;
Speak through the earthquake, wind, and fire,
O still, small voice of calm!
Comfort indeed for those oppressed by geology class.