was written to celebrate the meeting of Maximilian I’s Chancellor, Cardinal Lang, with the newly elected Pope Leo X in December 1513. This had especial relevance for Isaac since Leo was Giovanni de’ Medici, the son of Lorenzo the Magnificent his previous employer, and formerly one of Isaac’s own pupils. This first meeting of the Pope and the Chancellor was a political event of the highest importance, encouraging both Isaac and the unknown poet of the main text of the piece to strain every faculty for references and hidden meanings. The words, written in hexameters, include clever allusions: the ‘doctor’ of the opening lines is derived from the word ‘Medici’ through the Latin ‘medicus’; the ‘queen of birds’, which comes later in the first half, refers to the eagle in the imperial coat of arms; later still the ‘king of beasts’ is a pun on the lion or ‘Leo’, the Pope’s name. The librettist even sneaks in a reference to one of Maximilian’s main concerns of foreign policy – a war against the Turks. Isaac, for his part, undertook the doubly impressive task of setting his polyphony around two different plainchants, stated at the same time, each carrying texts relevant to the occasion, namely Da pacem
and Sacerdos et pontifex
. The chants are given complete in both halves of the motet, though, as was customary, this was done in diminution in the second part. Both halves end with the same words and similar music, the second statement splendidly extended into the most abstract pattern-music, a tribute to Isaac’s Flemish training.
from notes by Peter Phillips © 1991