Sung at the Sistine chapel at the end of Holy week, traditionally after midnight with candles gradually being extinguished. It became forbidden to transcribe it, punishable by excommunication, and there is a great story of Mozart writing it out from memory, then being summoned by the Pope – only to be praised for his amazing talent.
Written for 2 choirs – one sings a “straight” version, the other adds ornamentation, and this was not transcribed in early publisheds version, maintaining the mystery further.
Miserere mei, Deus: secundum magnam misericordiam tuam.
Have mercy upon me, O God, after Thy great goodness.
Boy treble needs to hit high C every other verse. But in some ways, the harder note to sing is the one that finishes the end of the phrase, which is not as high but v sustained…