There is only one theme underlying this programme, which is chant. We present this in three different ways: the 12th century interpretation of it by Hildegard of Bingen (these are her own compositions); the living Gregorian tradition as shown in these settings of the Salve regina and Nunc dimittis; and Arvo Pärt’s reimagining of this tradition, partly in the Orthodox view. 

In particular there is his Da pacem, where the alto voice quotes a whole chant melody, running from start to finish of the piece. For a thousand years, chant represented all there was of ‘classical’ music. 

It went on to influence some of the greatest music ever written in its image.“