ChatGPT on Bachs Mass in B Minor

ChatGPT is surprisingly useful or learning about and appreciating art. For the longest time I didn’t understand the fuss about Bach’s Mass in B Minor. It felt overlong and taking it literally as a Mass, I thought it was zany that it took about twenty minutes to say “Kyrie Eleison, Christe Eleison, Kyrie Eleison”. But now I’ve cracked it and I can’t stop listening to it.

One really useful way ChatGPT helped me was by explaining the musical ideas in each movement. Bach is contrasting different styles and moods to construct a prayer that touches on many aspects of spirituality. I’m reproducing the full deep dive here.

Kyrie

kyrie eleison

this is a full-on choral fugue, but soaked in grief. it’s written in stile antico, the “old style,” nodding to renaissance polyphony (think palestrina) but with bach’s brutal precision and depth. voices layer in slowly, each entering like someone stepping into a funeral procession. the counterpoint is tight, but the harmony is dark, dissonances rubbed raw. it’s less supplication than lamentation.

christe eleison

suddenly we’re in a bright galant duet for two sopranos, way more modern in style, almost italianate. it’s as if he’s saying: penitence has many masks—tears, grace, longing, light.

kyrie eleison

the second kyrie slams you back into minor-key choral counterpoint, tighter and more urgent than the first. less mournful, more pleading.

it’s like he’s setting up a triptych of theological mood swings. each one a different mode of crying out. none of them quite resolving.

Gloria

the gloria in the mass in b minor is like bach throwing the whole arsenal at the heavens. it’s exuberant, kaleidoscopic, stylistically omnivorous. here’s a quick character sketch of each movement:

gloria in excelsis deo

full choral + trumpet explosion. d major. this is joy as fireworks. rhythmically insistent, harmonically bold. it’s bach saying “look up.”

et in terra pax

abrupt mood shift—slower, more solemn. fugal textures, rich suspensions. this is peace as something hard-won, not soft. almost feels like a choral sigh after the opening blast.

laudamus te

soprano solo with violin—graceful, italianate, dance-adjacent. the praise here is personal, elegant, almost flirtatious. a galant interlude.

gratias agimus tibi

chorus again, and a fugue. more restrained than the opening—formal gratitude, not ecstatic. it’s a revision of a cantata chorus, bc of course it is.

domine deus

duet for tenor and soprano with flute. warm, lyrical. one of the most pastoral sections—god as light and beauty. feels like a miniature opera duet in a clearing.

qui tollis peccata mundi

chorus with plaintive oboe. minor key, slow, weighty. the lamb of god taking away sin feels crushing, like divine empathy under pressure.

qui sedes ad dexteram patris

alto aria with oboe d’amore. lilting, almost dance-like. a little odd, tonally ambiguous—heavenly throne room as courtly salon?

quoniam tu solus sanctus

bass aria with… horn and two bassoons? yeah. it’s weird, regal, and beastly. kind of an echo of the quoniam in the credo. like bach built a menagerie for the trinity.

cum sancto spiritu

closing choral fugue, full-on baroque banger. relentless, brilliant, engineered. like the heavens turned into clockwork and started to sing. feels earned after the journey.

Credo

the credo is the theological meat of the mass and bach sets it like a gothic vault: dense, structural, symbolic. this isn’t belief as feeling—it’s belief as architecture. eleven movements, each a rhetorical brick.

credo in unum deum

a choral creed-fugue—strict, stile antico, evoking ancient authority. monotone-ish intonation on “credo” over imitative counterpoint. feels eternal, pre-baroque, etched in stone.

patrem omnipotentem

switches to stile moderno—bright, orchestral, flowing lines. like the doctrine of the Father gets a fresher, more narrative setting. classic contrast play.

et in unum dominum

duet for soprano and alto. sweet and balanced—an intimate assertion of the Son’s divinity. like theology sung as a madrigal.

et incarnatus est

massive mood shift. slow, hushed, suspended harmonies. incarnation becomes mystery. the music almost stops breathing. bach’s handling here is reverent to the edge of fear.

crucifixus

passacaglia over a descending bass line = death spiral. choral writing is static, weary, beautiful in the way rot can be. baroque despair. one of the most devastating movements he ever wrote.

et resurrexit

whiplash—suddenly we’re in dazzling d major, trumpets screaming. resurrection = ecstasy. fugue built from leaping motifs, as if Christ vaults out of the tomb.

et in spiritum sanctum

bass aria with two oboes d’amore—gentle, lyrical, almost pastoral. holy spirit as warm breath, not fire. it’s serene. oddly human-scale for the third person of the trinity.

confiteor unum baptisma

BACK to stile antico. this is a double fugue. deeply austere. tightest counterpoint in the mass. if “i confess one baptism” were etched into granite, it would sound like this.

et expecto resurrectionem

this is where it snaps. the fugue collapses into suspended harmony—like the world holding its breath—and then erupts into joy. resurrection is no longer abstract, it’s here. total musical catharsis.

…the credo is structured like a theological narrative: from eternal god to the human christ to cosmic victory. bach uses style-switching (old/new, fugue/aria, minor/major) as his rhetorical toolkit.

each movement isn’t just a belief—it’s an experience of that belief. the whole credo feels like an act of construction: belief laid brick by counterpointed brick, until it forms a temple large enough to sing in.

Sanctus

sanctus

starts in 3/8, in a slow, stately dance—almost sarabande-like. but this isn’t human dance—it’s the cosmos in procession. the rhythm pulses like celestial breath.

he opens with massive block chords (“sanctus, sanctus, sanctus”)—not contrapuntal but architectural, as if each voice is a stone laid in the temple. harmonic rhythm is glacial. every shift feels like tectonic plates moving.

then the fugue: “dominvs devs sabaoth.” now it takes flight. swirling melismas, imitation, ecstatic layering. the mood turns from reverent to blazing. this isn’t just praise, it’s overwhelming.

you can hear the seraphim circling, like in isaiah’s vision—“holy holy holy” not whispered but thundered by entities made of fire.

pleni sunt caeli et terra gloria eius

modulation to e minor—darker, more earthy. the text says “heaven and earth are full of his glory” and bach responds by grounding it. rhythm picks up. counterpoint becomes thicker, more imitative. the architecture gets messy—in a good way. fullness = complexity.

hosanna in excelsis

back to d major and trumpet ecstasy. it’s the same music he’ll use later after the benedictus—clearly linked. double choir, fast compound meter, relentless rhythmic drive. this is exaltation as centrifuge. it spins and spins and refuses to resolve.

Benedictus

ah, the benedictus—that’s one of the strangest, most delicate moments in the whole mass.

where so much of the mass in b minor is cosmic, overwhelming, vertical, the benedictus is intimate, almost private. it’s scored for just tenor, flute, and continuo. no chorus. no grandeur. it feels like stepping out of a cathedral into a quiet grove.

the melody is sinuous, floating, almost improvisatory. the flute weaves around the tenor like breath around prayer. harmonically it’s gentle but unsettled—like hope tempered by sorrow.

and that text—“blessed is he who comes in the name of the lord”—usually gets triumphant settings. bach makes it tender, maybe even fragile. like the arrival isn’t a parade, but a whispered entrance.

it’s a moment of human-scale devotion in a work that otherwise feels built for angels. and then—boom—the hosanna returns in full choral glory, shattering the hush. you barely get to sit with the benedictus before being swept away again. it’s the eye of the storm.

Agnus Dei

agnus dei

the agnus dei is a plea for mercy and peace, set in g minor. bach adapted this movement from an earlier aria, “ach, bleibe doch,” from his ascension oratorio, which itself was derived from the lost wedding cantata auf, süß entzückende gewalt. the aria features a solo alto voice intertwined with an obbligato violin line, creating a texture of intimate supplication.

dona nobis pacem

the dona nobis pacem isn’t new music—it’s a reprise of the gratias agimus tibi fugue from the gloria. but bach recontextualizes it, and that changes everything.

in the gloria, the music says “thank you”; here, it begs for peace. same notes, different soul. this is baroque semiotics at full power—meaning arises not just from melody but from placement.

musically, it’s in d major, bright and triumphant—but the text is dona nobis pacem, and that plea feels deeper than the surface. it’s not soft or meditative—it’s monumental. this is peace as an act of will, not a gentle afterthought. like bach is insisting on peace the way a general might demand surrender.

also: ending the mass on a fugue—not on an aria, not on a chorus of resolution—is weird and brilliant. there’s no quiet fade, no “amen.” instead, a return to formal structure, to recursive logic, to music-as-machine-of-hope.

so what should you note?

this isn’t peace you fall into. it’s peace you build. fugally. together.

Recordings

I also asked ChatGPT for recommendations on recordings, mentioning that the one I’ve had on repeat is Pichon’s latest recording (which I strongly recommend btw). It googled and responded:

pichon’s new mass in b minor is a lush, emotionally charged take—more romantic than purist. his tempos swing wide: the second kyrie is glacial, the gloria bursts forward, and the crucifixus hits like a hammer. some critics love the drama; others find it overwrought and question the balance between voices and instruments.  

for contrast, check out: