The last movement of the Fourth Symphony is a setting of the poem Das himmlische Leben, a child’s vision of what life must be like in heaven. Mahler's whimsical and serene musical setting accompanies the soprano soloist with insrumental colors more typical of chamber music. Finally, the piece winds down to a pianissimo, in stark contrast to the earth-shattering endings of the first three symphonies.
Mahler originally intended to incorporate his setting of the Magic Horn (Wunderhorn) poem "Heavenly Life" (Das himmlische Leben) into his third symphony. However, the song finds a natural place at the end of the Fourth Symphony where its description of a child’s dream of what heaven must be like serves to heal all the previous movements’ conflicts. Throughout, the voice of the soprano soloist guides the listener like a beacon of light around which Mahler’s imaginative orchestral colors flicker joyfully: "Should a day of fasting come along, all the fish come swimming happily! There goes Saint Peer running with net and bait to the heavenly pond. Saint Martha will be the cook." His friend Natalie Bauer-Lechner recalled that in composing this movement "his mother's face, recalled from childhood, had hovered before his mind's eye; sad and yet laughing, as if through tears."