Saint François d'Assise

For maximum artistic freedom, Messiaen penned both libretto and score.[1] For nearly eight years, the composer consulted Franciscan sources, reading biographies by Thomas of Celano and St. Bonaventure, as well as Francis' own prayers (including Canticle of the Sun). He also cited passages from the Fioretti, Considerations on the Stigmata and the Bible.

In order to focus on the progress of grace in Francis's soul after his conversion, Messiaen omitted certain episodes in his hero's life, including the often-romanticized relationship between Francis and St. Clare, and the fable of his taming of a wild wolf at Gubbio.

Critics later chastised Messiaen for beginning the action after Francis’s conversion. The composer defended his choice in an interview with Claude Samuel: "Some people have told me, 'There's no sin in your work.' But I myself feel sin isn't interesting, dirt isn't interesting. I prefer flowers. I left out sin."[2]

The opera's eight scenes, divided into three acts, delineate Francis’s spiritual development. Act One contains scenes in which he realizes his goals: "La Croix" (The Cross), "Les Laudes" (Lauds) and "Le Baiser au Lépreux" (The Kissing of the Leper). Act Two shows Francis's journey towards enlightenment, ministry and divinity: "L’Ange voyageur" (The Journeying Angel), "L’Ange musicien" (The Angel Musician) and "Le Prêche aux oiseaux" (The Sermon to the Birds). The scenes of Act Three explore the saint's approach to divinity and his entrance into eternity: "Les Stigmates" (The Stigmata) and "La Mort et la Nouvelle Vie" (Death and the New Life).

Scene 1: The Cross

Saint Francis explains to Brother Leo that for the love of Christ he must patiently endure all contradictions, all suffering. This is the "Perfect joy."

Scene 2: Lauds

After the recitation of Matins by the Brothers, Saint Francis, remaining alone, prays that he might meet a leper and be capable of loving him.

Scene 3: The Kissing of the Leper

At a leper-hospital, a leper, horribly blood-stained and covered in pustules, rails against his disease. Saint Francis enters and, sitting close to him, speaks gently. An angel appears behind a window and says: "Leper, your heart accuses you, but God is greater than your heart." Troubled by the voice and by the goodness of Saint Francis, the leper is stricken with remorse. Saint Francis embraces him and, miraculously, the leper is cured and dances for joy. More important than the cure of the leper is the growth of grace in the soul of Saint Francis and his exultation at having triumphed over himself.

Scene 4: The Journeying Angel

On a forest road on La Verna an angel appears, disguised as a traveler. His knocking on the door of the monastery makes a terrific sound, symbolising the inrush of Grace. Brother Masseo opens the door. The Angel asks Brother Elias, the vicar of the Order, a question about predestination. Brother Elias refuses to answer and pushes the Angel outside. The Angel knocks on the door again and puts the same question to Brother Bernard, who replies with much wisdom. The Angel having gone, Brother Bernard and Brother Masseo look at each other, Bernard remarking, "Perhaps it was an angel..."

Scene 5: The Angel-Musician

The Angel appears to Saint Francis and, to give him a foretaste of celestial bliss, plays him a solo on his viol. This solo is so glorious that Francis swoons.

Scene 6: The Sermon to the Birds

Set at Assisi, at the Carceri, with a large green oak tree in spring with many birds singing. Saint Francis, followed by Brother Masseo, preaches a sermon to the birds and solemnly blesses them. The birds reply with a great chorus in which are heard not only birds of Umbria, especially the blackcap, but also birds of other countries, of distant lands, notably the Isle of Pines, close to New Caledonia.

Scene 7: The Stigmata

On La Verna at night in a cave beneath an overhanging rock, Saint Francis is alone. A great Cross appears. The voice of Christ, symbolized by a choir, is heard almost continually. Five luminous beams dart from the Cross and successively strike the two hands, the two feet, and the right side of Saint Francis, with the same terrific sound that accompanied the Angel's knocking. These five wounds, which resemble the five wounds of Christ, are the divine confirmation of Saint Francis's holiness.

Scene 8: Death and the New Life

Saint Francis is dying, stretched out at full length on the ground. All the Brothers are around him. He bids farewell to all those he has loved, and sings the last verse of his Canticle of the Sun, the verse of "our sister bodily Death". The Brothers sing Psalm 141. The Angel and the Leper appear to Saint Francis to comfort him. Saint Francis utters his last words: "Lord! Music and poetry have led me to Thee [...] in default of Truth [...] dazzle me for ever by Thy excess of Truth..." He dies. Bells ring. Everything disappears. While the choir hymns the Resurrection, a patch of light illuminates the spot where previously the body of Saint Francis lay. The light increases until it becomes blinding. The curtain falls.

Several leitmotifs exist in the orchestral score, most of which connect to one or more characters.

• Death (or "J’ai peur")

The dramatic action of the opera begins with the entrance of Brother Leo, who sings the "death" motif to words taken from the end of Ecclesiastes: "I am afraid on the road, when the windows grow larger and more obscure, and when the leaves of the poinsettia no longer turn red." "I am afraid on the road, when, about to die, the tiare flower is no longer perfumed. Behold! The invisible, the invisible is seen…" This theme repeats nearly every time Leo enters, and the orchestra accompanies it with lazy glissandos in the strings.

• Perfect Joy ("la joie parfaite")

Francis answers Leo's introspection with the "perfect joy" motif, a combination of Trumpet in D, xylophone and woodwinds. This motif reoccurs several times throughout the piece. In some cases, Brother Leo's "death" motif alternates with Francis' "perfect joy" motif.

• Solemnity

Messiaen linked Francis' moments of great solemnity with quite possibly the most pervasive motif of the opera. It is structured as a tone cluster in the trombone section, creating an ominous, harsh sound. The motif is quite evident in the second scene, wherein Francis asks God to let him meet a leper: "Fais-moi rencontrer un lépreux." The tone clusters break up his line of text: "Fais-moi"—cluster—"rencontrer"—cluster—"un lépreux."

• Grace

During Scene Four at La Verna, the Angel knocks on the monastery door. Messiaen represents the knocking with a motif heavy pounding sounds in the percussion and strings. He saw these knocks as an entry of grace—a force one must not resist. The Angel's knocking foreshadows Francis' eventual acceptance of the stigmata during Scene Seven. The main difference in Scene Seven is that the motif represents the painful, brutal pounding of nails into Christ's body.

Messiaen considered himself an ornithologist, and his love for birds is evident in the opera. The composer traveled to the saint's native Assisi, as well as New Caledonia, to research and record birdcalls of several local species, later transcribing them into melodies for use as musical themes attached to particular characters.

• François – Capinera (Italian for "Blackcap")

Upon entering caves at the Carceri (just east of Assisi), Messiaen heard the call of the capinera. Francis often retreated to these caves for meditation and prayer, thus the choice of the capinera is fitting.

• L’Ange – Gerygone

This yellow-bellied warbler from New Caledonia signals nearly every entrance and exit of the Angel. Messiaen scored the gerygone with a staccato piccolo alternating with glockenspiel and xylophone. In some cases, the kestrel birdcall accompanies the gerygone.

• Frère Elie – Notou

Francis' most contrarian brother, Elias, receives the birdcall of this "gloomy sounding pigeon" from New Caledonia.

• Frère Bernard – Philemon (or "friarbird")

The philemon birdcall (most likely recorded in New Caledonia) reflects Bernardo's age and wisdom while punctuating his musical and textual phrases.

Messiaen devotes the entire sixth scene ("La Prêche aux oiseaux" or, The Sermon to the Birds) to all manner of birdsong as Francis delivers his famous sermon with Brother Masseo in attendance.

Messiaen's full orchestration requires more than 110 musicians, placing great demands on budgets as well as orchestra pit space. At the Palais Garnier, the overflow of players were placed in boxes adjacent to the stage.

• Woodwinds: 3 piccolos, 3 flutes, 1 alto flute, 3 oboes, 1 English horn, 2 E♭ clarinets, 3 clarinets, 1 bass clarinet, 1 contrabass clarinet, 3 bassoons, 1 contrabassoon
• Brass: 6 horns in F, 1 small trumpet in D, 3 trumpets, 4 trombones, 2 bass tubas, 1 contrabass tuba
• Strings: 16 first violins, 16 second violins, 14 violas, 12 cellos and 10 double basses
• Percussion (5 players):

Player 1: bells, claves, eoliphone, snare drum

Player 2: triangle, claves, 6 temple blocks, very small cymbal, small cymbal, suspended cymbal

Player 3: triangle, claves, wood block, whip, a pair of maracas, a reco reco or guiro, glass chimes, shell chimes, wood chimes, tambourine, 3 gongs

Player 4: triangle, claves, set of crotales, large suspended cymbal, suspended cymbal, medium tom-tom, low tom-tom, 3 tam-tams

Player 5: set of bells, metal sheet, claves, geophone, eoliphone, bass drum

In addition to these, pitched percussion instruments are also used: one xylophone, one xylorimba, one marimba, one glockenspiel and one vibraphone, as well as three Ondes Martenot which the composer described in his interview with Claude Samuel as being 'very rare in an opera!'.

The opera requires a ten-part, 150-voice choir, which serves a twofold role: Greek chorus and divine presence. Throughout the piece, the chorus comments on Francis' spiritual journey. The first three scenes include a commentary on the preceding plot action with a "moral." For example, after Francis' conversation with Leo on "perfect joy", the chorus sings the text "He who would walk in my steps, let him renounce himself, take up his Cross and follow me." One could say that this text carries a double purpose—the moral is not only sung, but comes from the mouth of Christ. In the latter scenes of the opera, especially The Stigmata, the chorus perpetuates its image as Christ speaking directly to Francis as He bestows the wounds onto the saint. Messiaen's choral writing, especially the violent, wordless chants during The Stigmata, suggests a mystical, otherworldly presence.

Messiaen's synesthesia caused a perception of colors associated with particular harmonies or musical scale degrees. For instance, when hearing a C-natural on the piano, the composer saw "white" before his eyes. In the opera, Messiaen underscores the final moments (Francis' death and ascent into heaven) on a C major chord structure, providing a musical burst of white light. It is unclear whether this final chord structure was coincidental or intentional.