At the same time that this sense of perspective has been introduced into the polyphonic texture, a
similarly hierarchical sense of perspective orders the harmony as well. It is virtually taken for granted by
now that imitation will be “tonal” rather than literal. The setting of the text incipit (“Tui sunt coeli”), for
example, contains entries on the final (D) and on the tuba (A). In every case, the downward contour is
adjusted so that the two notes in question will define its limits: either A proceeds downward to D by way
of G (producing the intervallic succession step+fourth) or D proceeds downward to A by way of C
(producing the intervallic succession step+third).
In a way that is almost shocking for Palestrina, the next interval, while reversing direction as
expected, does so by means of a spectacular leap that emphatically requires a full “recovery.” The
ensuing stepwise melismatic “tail” (cauda) supplies precisely that. And it does not come to rest until full
recovery—return to the starting note—is achieved, which is how Palestrina is able to maintain melodic
tension over a considerable melismatic span, and why the tunes in his late compositions, however
decorative, always have a pressing sense of direction.
To pick one example: the altus, entering first, has to recover the whole sixth from B-flat to D in its
descending melisma; it proceeds immediately as far as E, but then reverses direction; it then overshoots
its top and skips down from C so as to require another recovery before it can go farther; that recovery
having been made, it teasingly moves down again to the E; finally it gives the ear what it craves, through a
circle of fifths; the D having at last been regained, the voice now—and only now—can rest. The line is
complex and tortuous, but as it keeps making and (eventually) keeping promises, it sounds at all times
purposeful, never meandering.
The high tonal definition and tonal stability established at the outset is maintained throughout the motet,
and the projecting and achieving of tonal goals are among the factors contributing fundamentally to the
impression of the music’s overall “shape,” the coherence of its unfolding. We are, in other words, just
about at the point where it makes sense to start replacing the old “modal” terms like “final” and “tuba”
(first employed some seven centuries earlier to assist in a purely melodic classification) with modern
terms like “tonic” and “dominant,” which refer to harmonic functions. The age of functional tonal
harmony, it can be argued, begins with pieces like this, although the full panoply of tonal functions will
not come into play until complete diatonic circles of fifths become standard—in about a century’s time,
and also in Italy.
The extraordinary lucidity and rational control that Palestrina achieved in his late work corresponds
quite closely with the ideals of the Society of Jesus, popularly known as the Jesuits, a religious order