Arvo Pärt came across a legend concerning the patriarch Agathon, from the 4th century, in a book containing stories of The Desert Fathers. They take us back to the cradle of Christian monasticism, in the Egyptian desert, the narrative telling of the meeting between the hermit Agathon and the leper. Agathon is tested several times by the leper. Not until after he has passed these tests does the leper reveal himself as an angel sent by God, and blesses Agathon.