Mahler's first four symphonies are often referred to as the "Wunderhorn" symphonies because many of their themes originate in earlier songs by Mahler on texts from Des Knaben Wunderhorn (The Youth's Magic Horn). The fourth symphony is built around a single song, "Das himmlische Leben". It is prefigured in various ways in the first three movements and sung in its entirety by a solo soprano in the fourth movement.
Mahler composed "Das himmlische Leben" as a free-standing piece in 1892. Several years later he considered using the song in the fifth and seventh movement, the finale, of his Third symphony. While motifs from "Das himmlische Leben" are found in the Third symphony, Mahler eventually decided not to include it in that work and, instead, made the song the goal and source of his Fourth Symphony. The Fourth Symphony thus presents a thematic fulfilment of the musical world of the Third, which is part of the larger tetralogy of the first four symphonies, as Mahler described them to Natalie Bauer-Lechner.