Tenebrae responsory

Responsories for Holy Week (Latin: Responsoria pro hebdomada sancta) are three sets of nine responsories, for Maundy Thursday, Good Friday and Holy Saturday respectively, the three days of the Holy Week preceding Easter Sunday. They are also known as the Tenebrae responsories, and were set to music for instance by Carlo Gesualdo (Responsoria et alia ad Officium Hebdomadae Sanctae spectantia, 1611) and by Jan Dismas Zelenka (ZWV 55).

The Night Hours (preceding the Little Hours) of Maundy Thursday, Good Friday and Holy Saturday consist of matins (each with three nocturns) and lauds. The lessons of these matins (three for each nocturn) are referred to as the Lamentations of Jeremiah the Prophet, although only those of the first nocturn for each of these services are from Jeremiah's Book of Lamentations: those of the second nocturns are derived from Saint Augustine (his commentaries on the Psalms), and those of the third nocturns from the Epistles.

As, until the 1955 reform of the Holy Week ceremonies by Pope Pius XII, these services were generally anticipated on the preceding day, the three groups of nine Tenebrae lessons (French: Leçons de ténèbres) are sometimes indicated by names based on Holy Wednesday, Maundy Thursday and Good Friday respectively, rather than on a sequence of names referring to Maundy Thursday, Good Friday and Holy Saturday respectively. The responsories following each lesson of these matins (so also 27) were usually sung, and these are the Tenebrae Responsoria, or the Responsories for Holy Week. The name of a collection of such responsories may also refer to the Holy Triduum, as in Orlande de Lassus' .

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