"Aestimatus sum," from the Holy Saturday Tenebrae Responsories of Carlo Gesualdo. Not entirely sad, but quite strange. Sort of like today. (And here's the whole playlist.)
Aestimatus sum cum descendentibus in lacum,
factus sum sicut homo sine adjutorio, inter mortuos liber.Posuerunt me in lacu inferiori, in tenebrosis et in umbra mortis.
Factus sum sicut homo sine adjutorio, inter mortuos liber.
I am counted with them that go down into the pit:
I am as a man that hath no strength: free among the dead.
Thou hast laid me in the lowest pit, in darkness, in the deeps.
I am as a man that hath no strength: free among the dead.
Attribution(s): "Bell Tower" (source) via CC BY-SA 4.0.