Audio, full demo: hymnal version (accompanied then a cappella), free harmonization, harmonized descant. Free score.
John Mason Neale's hymn "O very God of very God" borrows from the incarnational statement of the Nicene Creed, and focuses on the second phrase, 'very light of very light.' Each of Neale's five verses addresses light, dawn, rising, daylight, Sun (his capitalization). In particular, the references to light conjoin with 'till thou shalt come' to make this text particularly appropriate for the Fourth Sunday of Advent, the most proximate to the winter solstice. (In his third series of Hymns for Children (1854), Neale assigned this as the analog to the 'O Antiphon' for December 21, O Oriens.) More generally, this hymn enjoys a season approaching the vernal equinox, especially the "gesimas," the Sundays immediately preceding Lent, as well as Lent itself, a word derived from old English referring to the lengthening daylight: 'and even now, though dull and gray, the east is brightening fast.'
BANGOR was originally written as a three-part metrical setting to Psalm 12 (1734) and Psalm 11 (1738), by William Tans'ur, an English composer whose oeuvre includes a prodigious number of hymn tunes and Psalm settings. He had a profound influence on the early New England sacred composers such as William Billings and Oliver Holden, who like Tans'ur, were not formally trained for their life's musical passions. This tune first appeared in his volume A Compleat Melody; or the Harmony of Zion in 1734.
There's an illuminating story about the tune in the Bangor Daily News (the other Bangor). There is also a second article.
Hymns and Carols of Christmas: Christmas in Neale's Hymns for Children
slight rev. 2019 to ad lib bridge
O very God of very God
We wait in faith
and turn our face
to where the daylight springs;
Till thou shalt come
our gloom to chase,
with healing in thy wings.
John Mason Neale
Hymns for Children, A Third Series, 1854
Descant for the choirs of St. Peter’s Episcopal Church, Cambridge MA