Why do priests wear vestments at Mass? (Glad you asked: Q&A on church teaching).

I remember as a kid watching my dad make a classic Windsor knot in his tie. "Out of the hole," he would whisper as he tied, "around the tree, into the hole.... "The ditty traced the scrambling of a fictitious rabbit and was a kind of parable my dad learned to help him remember how to tie the mysterious knot.

In the same way, our priest, Father Kelly, would whisper an incantation while he tied his own mysterious knot: "Praecinge me, Domine, cingulo puritatis...." He was securing the cincture, an ornate cord he wore around his ample waist at Mass. It symbolized the chastity for which he was praying and was part of the indispensable vesture of priests before Vatican II. In all, priests wore the amice, alb, cincture, maniple, stole, and chasuble. Throw in the tunicle, dalmatic, cope, buskins, mitre, pallium, succinctorium, and fanon worn by various clerics from deacons to the pope, and you had quite a wardrobe of liturgical duds. It's a wonder the guys could even breathe!

Each vestment was supposed to symbolize something--from protection against evil (the amice) to eternal life (the stole). Time, however, conspired to place the cart before the horse. The need for symbols did not bring about the existence of the vestments: It was the other way around.

Back in the days of the Roman Empire, when Christians first gathered for liturgy, the presider simply wore his or her (yes, her) regular street clothes. If you saw last year's smash hit movie Gladiator, you have some idea of how ancient Romans dressed for success. Those flowing robes were pretty much what a presider would wear at liturgy. And it wouldn't have been unusual for that early assembly to chip in and buy some really nice threads to distinguish their guy.

Now consider the frequency with which those early Christian leaders got thrown to the lions. Hoping, of course, that when they went, they were wearing their old clothes, the community would naturally pass on the glad rags to the next guy. And so on. Eventually, all the clothes worn by presiders were the hand-me-downs of their predecessors. So, while styles of dress evolved, the vestment of the presider didn't. After the church went legit in the fourth century, the style became legislated.

Today, priests are required to vest in an alb, the white robe that reaches to the floor; a stole, the long scarf worn over the shoulders; and a chasuble, the flowing, ornate garment worn over everything. In a church that celebrates an unchanging faith in an unbroken tradition, vestments preserve the style of our ancient Roman beginnings. Allowed to evolve, they would simply have become the shirt, tie, and jacket my lather wore. Conserved, they remain the distinguishing garb of the liturgical presider.

By FATHER PAUL BOUDREAU, a priest of the Diocese of Norwich, Connecticut and author of Between Sundays: Daily Gospel Reflections and Prayers (Twenty-Third Publications) and a regular columnist for Today's Parish magazine.