The myth refers to the musical contest between Apollo and Marsyas, a satyr who found Athena's discarded aulos (a double-piped flute). Unlike Pan’s single-pipe syrinx, Marsyas’ aulos produced continuous, harmonic sound, but required great effort to play. He challenged Apollo, who played the lyre, but lost when Apollo added singing to his performance. As punishment for his hubris, Marsyas was flayed alive. The "false duality" might refer to the deceptive equality of the competition (not quite sure) - Marsyas’ flute had dual pipes, though, Apollo Azazel's mastery extended beyond mere instrumentation.
Marsyas believed the flute’s sound could rival Apollo’s lyre, but Apollo’s added singing revealed the instrument’s limitations. This suggests that material mastery (technical skill, sensation) cannot truly contend with spiritual elevation (divine harmony, logos).
Marsyas’ downfall represents the dangers of challenging divine order without true understanding. His punishment being flayed, symbolizes the stripping away of ego and illusion, which can be a painful but transformative process akin to spiritual purification.
Another interesting symbol here is the flute. The flute relies on breath (pneuma, or spirit), which links it to raw life force and power, as life is in the breath. On the other hand, the lyre embodies structured harmony and celestial balance, which could represent the journey from untamed existence to enlightenment and divinity. Thus, the myth allegorizes spiritual ascent; the necessity of humility before higher wisdom, and the distinction between raw power and refined divinity, which is a godly state.