The word pneuma comes from the Greek word for "that which is breathed or blown." The term took on multiple layers of meaning for the ancient Greeks and later for Judeo-Christian theologians and philosophers, as it became a word for "spirit" or "soul."
References to the "breathe" concept are found in the song's line We are born of one breath, one word, and the continued repetition of "spirit."
In the case of this song, the reference to the word is clearly oriented towards the yogic tradition, with guitar synthesized to sound like the Middle Eastern sitar and the light playing of Arabic goblet drum. Breath, or "pneuma," is at the core essence of yogic practice, both literally and spiritually.
This song basically is a yogic meditation rendered in music. It discusses how we human beings are bound to our flesh and the illusions of the material world, but really are called to return to the essential, egoless "pneuma" of the universe's underlying reality. The song is a call to spiritual freedom and oneness:
Reach out and beyond
Wake up, remember
We are born of one breath, one word
We are all one spark, eyes full of wonder