It is not quite certain that this poetic little piece is by Byrd, but stylistically it seems to bear the melodic and harmonic hallmarks of his early works. It could have been composed at any time during Mary Tudor’s reign (1553-1558) but survives anonymously in the same early keyboard manuscript that preserves the composer’s two Miserere
settings (BK66/67), and was copied in the early Elizabethan years, at the latest. By the start of Elizabeth’s reign, Byrd had probably already composed three other pieces based on the same plainsong melody of the Catholic Sarum (Salisbury) hymn Christe qui lux es et dies, / Noctis tenebras detegis; / Lucisque lumen crederis, / Lumen beatum predicam
(‘Christ, you who are the light and the day / roll back the shadows of the night; / you are believed in as the light of light, / foretelling blessed light’). These three settings now survive as consort works, in versions that may possibly have been intended to give a second life to even earlier pieces that were originally liturgical works to be sung for the Sarum rite and had no formal function after Queen Mary’s death in 1558.
This organ setting of the same plainchant has some features in common with one of the consort ones, so the likelihood that it is by Byrd is strengthened. It would still have been useful during Byrd’s years as organist at Lincoln Cathedral in the 1560s. The plainsong is clearly audible in the top voice. Below it, two voices (tenor and bass) set up a gentle dialogue. The first phrase of three bars is followed by a similar answering one that however leads the music to a different cadence. The third phrase is much longer and more involved, leading the top voice to abandon the strict plainsong in steady notes towards the end. Finally, for the last phrase an extra voice (alto) is added, bringing this luminous little work to a fine close. Christe qui lux would have been liturgically appropriate at the quiet evening service of Compline, during Lent. It is here played twice, at 10’ pitch and then at 5’ pitch.
from notes by Davitt Moroney © 1999