très lent, celestial

Very slow, celestial — Messiaen's most characteristic slow tempo marking, typically applied to meditative passages of great stillness in which long melodic lines unfold above sustained resonances.

Duration is the primary material in très lent passages. Avoid any sense of hurry — these are moments of expanded, contemplative time. Let harmonics accumulate with the sustain pedal, then clear decisively before each new harmonic area. The celestial quality depends on absolute tonal control and an absence of physical tension.