I suspect the aesthetic is being referred to. Which would extend to more than just music.
Christian Liturgy has always been a fusion of form and function.
-CryptoLutheran
I think liturgical beauty is more than just aesthetics, so I was not only referring to the aesthetics of the service. The beauty of the liturgy has a divine quality which is intrinsic, and there are certain common features which every valid liturgy should have, for example, certain parts of the services of Baptism and Holy Communion, and certain prayers, for example, one expects to see the Lord’s Prayer in every liturgy, and I do not believe that prayers can be considered a field aesthetics, even though they do have elements of literary style and poetry.
Additionally I also am of the view that any truly beautiful liturgy will not have formal components devoid of function. Which may at first seem like an odd view, considering that I regard the Byzantine, Syriac Orthodox and Coptic liturgies as the most beautiful, and these three liturgies are also the most ornate, and likewise I love the traditional Latin mass, which differs from the Novus Ordo chiefly in terms of being more ornate. However, these elements, which some people believe are accretions, aren’t; if one studies the liturgy in detail, one will discover that they all have important meanings and are important components of the entire liturgy, as opposed to optional extras which could be eliminated for the sake of simplicity.
Furthermore, it is my considered opinion, based on my study of the history of liturgical service books, which is in turn based on readily availble texts,, that liturgical accretions are mostly a myth; the only actual liturgical accretions I have found that could be regarded as spurious, problematic and worthy of removal are some of the elements present in the problematic Divine Office of the Roman Rite before the reforms of Pope Pius X, which were specific to that version of the Divine Office, and not to the version used in Benedictine and other monasteries, nor the Dominican Rite divine office, nor the Office of the Dead, and also there were a few other problems, for example, the overriding of ferial Sundays by minor feasts disrupting the reading of the lectionary. But for the most part, the phenomnenon of accretions is a mirage; an illusion that people came to believe in due to a misunderstanding of certain early liturgical service books:
In the West, you see, starting with the Missal, all parts of the liturgy said by anyone were consolidated into one book. This was partially due to the adoption in the Roman Catholic Church of a curious liturgical practice wherein the priest repeats in prayer all of the propers and responses in the liturgy, so the priest is actually praying everything, and this historically was not the custom in the Roman Rite (and I am not sure if it is an aspect of the Novus Ordo or not), and also, no other liturgy does it.
Outside of the Catholic Church, the historic arrangement of service books remained prevalent much longer, and in this system, liturgical books contained only the content specific for a given user. Thus the Euchologion of St. Serapion of Thmuis, or the Anaphora of the Apostolic Tradition, appear simpler than the versions of the Alexandrian and Antiochene liturgies in use today (and most people do not realize the Anaphora of the Apostolic Tradition, also known as the Anaphora of Hippolytus, although St. Hippolytus almost certainly did not write it; rather I suspect he quoted it, since it seems likely that even in the third century the Antiochene type of liturgy was the most common) has been in continual use since the fourth century in the Ethiopian Orthodox Church.
Now the confusion derives from the fact that, due to the influence of the Roman Missal and other service books structured along the same lines, it turned out to be very convenient to have the entire liturgical text in one book, so this became increasingly common across multiple ancient churches, but what this did is it simply resulted in the texts increasingly including more detail, that did exist previously, but which was not defined in the same volume. So if we look at the version of the Anaphora of the Apostolic Tradition in use in the Ethiopian Orthodox Church, which they call the Anaphora of the Apostles, one will find a much more fully fleshed out liturgy than the very skeletal text provided by St. Hippolytus, but context is everything: like the Euchologion of St. Serapion of Thmuis, the text of Hippolytus was intended for use by bishops, and thus only included the parts of the liturgy said by the celebrant, and the immediate responses to it.