(P.77) is a musical setting of the sequence, composed by Giovanni Battista Pergolesi in 1736. Composed in the final weeks of Pergolesi's life, it is scored for soprano and alto soloists, violin I and II, viola and .
The autograph manuscript of the work is preserved in the Benedictine Abbey of Monte Cassino.
Many pieces which were said to have been composed by Pergolesi have been misattributed; the is definitely by Pergolesi, as a manuscript in his handwriting has been preserved. The work was composed for a Neapolitan confraternity, the , which had also commissioned a Stabat Mater from Alessandro Scarlatti. Pergolesi composed it during his final illness from tuberculosis in a Franciscan monastery in Pozzuoli, along with a ' setting, and finished it shortly before he died.
The is one of Pergolesi's most celebrated sacred works, achieving great popularity after the composer's death. Jean-Jacques Rousseau showed appreciation for the work, praising the opening movement as "the most perfect and touching duet to come from the pen of any composer". Many composers adapted the work, including Giovanni Paisiello, who extended the orchestral accompaniment, and Joseph Eybler, who added a choir to replace some of the duets. Bach's ' is a parody cantata based on Pergolesi's composition.
The work was not without its detractors. Padre Martini criticised its light, operatic style in 1774, and believed it was too similar to Pergolesi's comic opera ' to adequately deliver the pathos of the text.
The work is divided into twelve movements, each named after the of the text. Much of the music is based on Pergolesi's earlier setting of the sequence.