The only continental Mass, as it happens, that is in any significant way comparable to Byrd’s settings
is the Missa Papae Marcelli, where Palestrina had also, if for very different reasons, adopted a cell-or
module-oriented technique of composing, playing imitation off against homorhythm. Since the most
revealing comparisons are those that discover difference in a context defined by similarity, it will repay
us to concentrate on the same two sections from Byrd as we did from Palestrina: the Credo and the Agnus
Dei (Ex. 16-17). And the first difference we discover is that where Palestrina had segregated the two
techniques (systematic imitation, declamatory homorhythm), Byrd integrates them with singular terseness
and word-responsiveness.
The contrast shows up particularly in the Agnus Dei, where the one by the official Catholic was
contrapuntally rich and calmly imposing, the ones by the closeted Catholic (besides being leaner, not
necessarily by choice) are rhetorically complex and restlessly significative. “Restlessly,” because the
rhetoric and the signification of the setting changes radically, as Kerman has keenly observed, from Mass
to Mass. To make the comparison finer yet, then, let us contrast Byrd with Byrd as well as Byrd with
Palestrina.
MUSICAL HERMENEUTICS
The Mass in Four Parts, the earliest of the settings, was composed almost immediately after Byrd’s
second volume of protest-motets was issued, and retains something of their tortured mood. The mode—
transposed Dorian, but with a specified E-flat that “Aeolianizes” it into something more nearly
resembling plain G minor—contributes to the mood, of course; but more potent by far is the astonishing
degree of dissonance, which grates most where it is least expected, in the Agnus Dei, a text outwardly
concerned with gentleness, deliverance from sin, and peace.
Byrd’s setting, unlike practically any continental setting, is one continuous piece, not a triptych. The
three invocations of the Lamb, all strictly if concisely imitative in texture, are nevertheless distinguished
from one another by the progressive enrichment of their “scoring”: the first for a duo, the second for a
trio, and the last, with its new words (dona nobis pacem, “grant us peace”) for the full complement. It is
when those very words are reached, amazingly, that the voices begin rotating in a stretto based on a
syncope, and the dissonance level—a suspension on every beat, emphasizing the sharpest discords (major
seventh, minor second, minor ninth)—begins to approach the threshold of pain. The music (Ex. 16-17) is
unprecedented both in its sheer sensuous effect and in its exceptional rhetorical complexity.
EX. 16-17 William Byrd, Mass in Four Parts, Agnus Dei, mm. 40–56