The Reformation was, of course, the source of the dichotomy between the elaborate Catholic aesthetic and the simple, even harsh, Protestant one. It’s remarkable how persistent this difference has been: the divide between the adornment still seen in contemporary Catholic churches and the bare walls and black curtains of the contemporary Reformed church (many traditional Protestant churches have quite sensibly defected to the Catholic side on this issue) is at least as marked as the difference between Catholic Flemish art and Reformed Dutch art in the seventeenth century.
As with all things associated with Catholicism, Reformed people look warily upon adornment in the church. Catholics, I suppose, might think of Protestant churches as being dull and joyless in appearance (I know I do), but the Reformed view of fancy Catholic buildings and, in particular, vestments is more condemning. Many of them believe that ornate vestments show that the Catholic church is full of opulent excess centered around glorifying themselves. (To see this view in action, watch the Luther movie.)
This is clearly a violation of AGI, attributing a bad intent to a tradition that has countless other possible meanings. It’s also provably false: the traditional clothing for priests not celebrating the Mass is the black cassock and white clerical collar, as simple and humble as can be. The vestments are only worn while the priest is performing the liturgy.
The vestments, then, serve the opposite purpose of glorifying man: being worn only when the priest is acting as a representative of God, they actually represent the glory of God. This makes sense. If you were meeting with an emissary from the king of a grand kingdom, you would be surprised if he were dressed as a peasant. His clothing should befit the king that he represents. The emissary himself isn’t a great or rich man, but he is the closest you are going to get to seeing the king. Thus also with vestments.
Within the Mass, vestments add to the beauty of the service, a glimpse of the beauty, joy, and richness of worship in heaven. Last but not least, vestments are pretty and help make Mass something you might actually want to go to, as opposed to something staunch and dull, preached in a dress shirt, tie, and brown slacks.
Naturally, I am in favor of vestments. Why wouldn’t you be?
If you’re curious, the paintings are “The Lion Hunt” by Peter Paul Rubens and “The Milkmaid” by Johannes Vermeer, both from the mid-1600s.