This setting of the mass is dated 1822, and was revised in 1826. Leo Black, the Schubert schola, identifies this mass setting as one of the works where Schubert reflects on life and death. It is thought that he felt this to be the best of his mass settings.
There are four earlier mass settings dated 1814 to 1816, and this work is a departure from their shorter style. It is scored for SATB soloists and choir, strings, woodwding (flute, 2 oboes, 2 clarinets, 2 bassoons), brass (2 horns, 2 trumpets, 3 trombones playing Alto Tenor and Bass vocal parts), timpani and basso continuo.
A good summary of the mass setting can be found by Blair Johnston:
The usual six portions of the Mass Ordinary are all in place: Kyrie, Gloria, Credo, Sanctus, Benedictus, and Agnus Dei.
The Andante con moto Kyrie begins with mild woodwind thoughts that are soon enough duplicated by the chorus; the movement’s central, “Christe eleison” portion is, as per tradition, assigned to the four vocal soloists.
There is something positively symphonic about the Gloria (Allegro vivace e maestoso). The choral writing is very frequently the poor sister of the orchestral music that “supports” it. The soloists again come out of the woodwork during the “Adoramus te” section, perhaps to prepare themselves for the more extended soloism of the central “Gratias agimus” – calm music that sounds almost as though it might have been conceived for string quartet. The Gloria culminates in a large fugue.
The Credo opens in a solid and self-assured C major. There is a stunning pause and then sudden drop down to an A flat major chord for the throbbing “Et incarnatus est.”
The Sanctus (Andante) is absolutely stunning in its first bars, as what seems to be a confident F major pulsation in the orchestra is sharply undercut by the chorus’s decision to enter in F sharp minor. The movement as a whole is one of those movements in Schubert’s music where the world of Romantic harmony seems to take shape.
Both soloists and chorus are given their fair share in the Benedictus, likewise in the Agnus Dei that concludes this wonderful mass; the final moments of the mass are ones of refined exultation, eventually melting down into a few lyrical woodwind twists.
https://www.allmusic.com/composition/mc0002373376
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