Why do priests wear vestments during Mass?

Answer 1

There are several different reasons why priests wear uniforms, known as vestments, during mass. Different vestments can indicate the level the priest has in the church. For example, the vestment of a monsignor priest and a cardinal are very different. Along the same lines, if you ever see a priest outside of the church you will notice he will wear the clerical collar. This is to show that he is a priest. Similarly, in the church there is no question as to who is a priest, who is a deacon, and who is a lay person. The color of the vestments are also significant. Each color indicates what Liturgical season the church is in. For example, a green vestment indicates the church is in Ordinary Time and a violet vestment would indicate the church is in Lent or Advent. Uniformity is another reason why priests wear vestments. The word catholic means "universal" and the Catholic church has set up their Liturgical calendar (note that other Liturgical churches do this as well) and their masses to be performed in a certain order. You can go to several different Catholic Churches in several different locations and the priests will always be wearing vestments that reflect the Liturgical season and the mass will always have the same order. You will never see a Catholic priest dressed in an aloha t-shirt and jeans while performing a mass. The church wants to present itself in an orderly fashion and having priests wear similar, formal attire is one way to do it. Probably the most important reason comes down to respect and tradition. If you look at many ancient religions you will find that certain attire was worn during different ceremonies. It was a sign of respect to the Gods, after all you are in their house and you are most likely there to thank them for something they have bestowed upon you. When you go to a job interview what are you going to wear? The best option would probably be something that is formal like, for a man, a suit and tie. Why would you do that? Well, in our society a suit and tie is a formal, respectable piece of clothing and shows that you care about how you present yourself. The same goes for religion. The priests, like that of the ancient religions, are wearing a formal attire that in the tradition of the church (stemming back to the Old Testament Jewish priests) was deemed appropriate. The Catholic Church in the past would even kick people out of church for not wearing appropriate clothing. It has been only recently that churches have allowed their pastors to dress down in order to not only appeal to the younger, more casual generations but to also be separated from Liturgical churches, which are often deemed to be "too Catholic."

Answer 2

Catholic AnswerThe short answer is because they have to, and to give glory to God. The long answer is that the use of distinctive clothing for the priesthood goes back to God's commands to the priest of Aaron in the Old Testament. In particular, it is Our Blessed Lord, Himself, who is celebrating Mass through the person of His Priest, and the Vestments are a way of showing this, and showing that he, the priest, is distinct from the congregation, and that what he is doing is through the power of God, and distinguished from anything secular.