A ‘Requiem’ is a mass for a dead person. Composers wrote a lot of music to be played in masses, including this type. The lyrics are religious and part of the liturgy (secuencia, ofertorio, comunión).
Mozart didn’t complete his Requiem in D minor, so there are many versions by several composers, who tried to finish it.
One of the most amazing parts is the Dies Irae, based on the gregorian chant of the same name:
The Lacrymosa is also a beatufil and heartrending part. With these images the author wants to show what she feels when listening to Mozart’s Lacrymosa.