About this work
Thomas Tallis' first known job as a musician was playing the organ for a Benedictine priory in Dover from 1532, just at the outset of the English Reformation. Over the course of more than 50 years, the prodigious (and flexible) musician played the same instrument for at least five institutions: abbeys, churches, cathedrals, and, ultimately, the Chapel Royal of the English monarchy. Unfortunately, relatively little of his organ music survives from this lengthy career. The surviving fraction consists of a small handful of partsong arrangements, and a few more keyboard arrangements of liturgical hymns and antiphons. Each piece thus becomes a precious window into what the man's daily musical life must have been. It seems that at least some of his jobs required the organist to play -- possibly improvising much of the time -- arrangements of certain liturgical items. An organist could embellish an antiphon to play before the Magnificat, or he could alternate hymn verses with the choir. In each surviving piece, Tallis bows to liturgical propriety and includes the proper plainchant as a long-note cantus firmus in one voice. It seems safe to conclude that the written-down examples of such music reflect something of his common practice, though they may perhaps be more polished exemplars.
Tallis' Jam lucis orto sidere is his only surviving piece of liturgical keyboard music not composed for a festal liturgy such as Easter or Christmas. The hymn itself serves the morning Office of Prime on ordinary Sundays throughout the church year. It may then be the case that he became so familiar with the tune he was able to improvise or arrange fairly elaborate settings. In this case, Tallis places the chant melody (melody from the English Sarum Rite) in the tenor voice in the midst of the texture, and varies it somewhat with rhythmic alterations and other embellishments and bridges between phrases. Around this central liturgical tune he weaves a relatively dense polyphonic texture. Specifically, all four phrases of the chant melody are surrounded by a fantasia-like web of tight imitation on a single motive, which appears on almost every note of the scale. He concludes each verse with an elegant little triple-meter flourish.