"The aim of this brief treatise is to give a simple and clear account of the essential characteristics of Byzantine sacred music, the purposes which this music is intended to serve, the spiritual and other conditions requisite for rendering it properly, and the spiritual and other qualifications of Orthodox ecclesiastical chanters" (Constantine Cavarnos, from the preface).
This 31 page booklet, including endnotes and index, is a single essay, divided into four short sections, followed by "Select Statements of Eastern Fathers Concerning Psalmody." It was originally published in 1956, and has been reprinted in its original form.
As a relative newcomer to the Eastern Orthodox Church, coming from 30 years as a guitar player, worship leader and choir director in various Protestant churches, I've been looking for a simple introduction to Byzantine music for a few years. This booklet is what I've needed.
Here we learn that Byzantine sacred music is characterized "by simplicity from undue complexity, by purity or freedom from everything sensual, ostentatious, insincere, and by unsurpassed power and spirituality."
Cavarnos writes, concerning the spiritual aim of this music, that it is "in the first place, a means of worship and veneration; and in the second place, a means of self-perfection, of eliciting and cultivating man's higher thoughts and feelings and of choosing and eliminating his lower, undesirable ones."
He provides a brief background, from biblical and early church sources, on the role of hymn singing and psalmody in the worship setting. Of particular interest to me was his short explanation on why Byzantine church music does not make use of musical instruments.
He quotes G.I. Papadopoulos, who writes: "The Fathers of the Church, in accordance with the example of the psalmodizing of our Savior and the holy Apostles, established that only vocal music be used in the churches and severely forbade instrumental music as evoking pleasure without spiritual value." At one time, I would've argued strenuously against this latter statement, but having immersed myself in this worship tradition for several years now, I see great wisdom and truth in it.
Among the choice quotes at the back of this booklet is the following one from St. Gregory of Sinai:
"God is peace, beyond all tumult and shouting. Our hymns, accordingly, ought to be angelic, without tumult."
Interested readers may want to try to get their hands on the sequel to this booklet, "Byzantine Chant," also by Constantine Cavarnos.