Ecclesial music within the Eastern Orthodox Church (and in the Oriental and Assyrian Orthodox Churches) can trace its origins and inspiration within the musical traditions of ancient Greece and the Middle East. From these sources and their complex mathematical musical scales, along with the liturgical life of the Jewish synagogues in which the first Christians came from, developed a particular liturgical music.
A music whose focus was to not overwhelm the gathering of faithful with excessive melody and send them into a trance; nor to cause them to tune out from sheer boredom by excessive emphasis on words and silences. The musical forms and expression of liturgical worship sought to bring the faithful into a state of meditative contemplation and prayer that had its chief aim of worship (doxology) of God.
Of course this particular liturgical musical heritage was not specific to the Eastern Christendom, but was commonplace across all of Christendom and was the form in which Western Christians also worshipped in their liturgical services, as evidenced by Ambrosian, Mozarabic, Old Roman and Celtic chant.