Perhaps the best known penitential chant in the Gregorian repertoire, since the 10th century and until a few decades ago it was sung by the people of God throughout Lent. This is the first time in history, as far as we have records, that a performance of this piece is turned into an NFT. In addition, this NFT contains the only copy of the performance of the work. The file will be destroyed after mining, to make this NFT an absolutely unique piece.