They are not necessary for validity or efficaciousness of the sacraments or liturgy. But they are necessary under the law and the authority of the Church. A priest who fails to vest, or vests incorrectly for a liturgy is guilty of a violation of the law. It must be stressed that this is disciplinary and not doctrinal. The Church is not necessarily infallible in its discipline. But the fact that vestments are stable over long periods of time, with the approval of bishops in communion with the Holy Father, is proof positive that it is a right discipline and not in error.
Here is a Catholic Answers tract explaining the Scriptural underpinnings of vestments.
As for when God told us to use vestments and whom He spoke to, you will not find dramatic stories like those of Exodus in Holy Tradition, but you will find ample evidence of the Holy Spirit’s movement in the Church, which regards Tradition as the inspired Word of God just as Scripture is.
Redemptionis Sacramentum is the newest document which contains specifics about what vestments should be used and when. It is an instruction, in a much dryer tone than the vivid Biblical stories that Fundamentalists know and love, but it is an official Church document and has all the force of liturgical law. In it, you will find citations which mostly refer to the Roman Missal, which is itself part of Tradition, and of course the codification of the perfect prayer of the Mass.
Actually, the Apostolic age is over and long gone. What we have in modern times is Living Tradition and Apostolic Succession, which has handed down the vestments in use by the Western and Eastern Catholic and Orthodox Churches today.
I want to thank you for this detailed response- this particular one wasn’t in direct response to one of my posts, but it has helped me to see quite a bit more of where you’re coming from. I’ve been trying to find the right way to respond, and I am going to give it a try here.
What I’ve said to this point- that God told Moses how Jewish priests should dress, exactly what the Temple should look like, all the details about sacrifices and the Ark and so many other things- I’ve contrasted this with the lack of a particular message to a particular Christian in order to argue for divine indifference. God doesn’t have a particular preference for the color you should paint your kitchen, any more than God has a particular preference for the color or design of a Christian place of worship. I argue that God displays indifference toward jean shorts and fishing hats in the same way that He displays indifference toward how Christian clergy ought to dress.
This attitude happens to match my own indifference toward all these things, but my indifference and the indifference of my general tribe of Christians is not the ground on which this argument for indifference is based. It is based on what God has done or not done, and it is based on what can be reasonably expected of God when He is or is not indifferent toward something.
Now, the Catholic Church did not initially care about how priests and/or bishops dressed. Initially, they were indifferent. Then they stopped being indifferent, and pretty much all Christians started to care. A tradition was established, a few of them actually, and it became rather permanent. The people associated with those traditions have cared about their clergy dressing a certain way ever since.
I’m going to argue that it’s possible, even likely, for God to continue being indifferent about something even when all or most of Christianity has decided to care about it very much. I realize this is antithetical to both the Catholic and Orthodox way of thinking, but I do not automatically assume that when the Church cares about something, God also starts caring. If you ask me, it is possible for the Church to be indifferent toward something then establish a solemn and permanent tradition of caring, all while God continues to be quite indifferent as He always was.
Again, I do not look to my own tradition as the ground for this argument, and I suggest that you question whether you really have that good of a reason to look to yours as the sole ground for arguing for or against God’s indifference. At the very least, I’d like for you to ask yourself why I should look to your tradition as if it has some formal equivalence with the mind of God.
Rather, when my judgment (or anyone’s judgment) is based on God’s behavior and the things He has to say for Himself, it is most reasonable to conclude that God displays a divine indifference toward the clothing that Christian clerics choose to wear, whereas some traditions within Christianity may grow (and have grown) to care about it far more than He does.
There is nothing wrong or particularly damaging in caring about this so much. However, I do think it’s false to say that God cares as much as you do, and I also say that if your argument to the contrary consists of “We care, and we really feel like the rules should reflect that God must care in the same way that we do,” this argument is not particularly useful or convincing, especially to an Evangelical like me.
In short, there’s hardly any use arguing for this unless you already think you can gain a convert. It’s not the sort of thing you’re likely to convince someone of if they are outside your particular tradition, because the impressiveness of your own tradition is the sole ground for…well, for itself, and there is no particularly convincing evidence grounded in what God Himself has said or done.
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