"For every high priest is appointed to offer gifts and sacrifices; hence it is necessary for this priest also to have something to offer. Now if he were on earth, he would not be a priest at all, since there are priests who offer gifts according to the law. They serve a copy and shadow of the heavenly sanctuary; for when Moses was about to erect the tent, he was instructed by God, saying, “See that you make everything according to the pattern which was shown you on the mountain.” But as it is, Christ has obtained a ministry which is as much more excellent than the old as the covenant he mediates is better, since it is enacted on better promises. For if that first covenant had been faultless, there would have been no occasion for a second. For he finds fault with them when he says: “The days will come, says the Lord, when I will establish a new covenant with the house of Israel and with the house of Judah; not like the covenant that I made with their fathers on the day when I took them by the hand to lead them out of the land of Egypt; for they did not continue in my covenant, and so I paid no heed to them, says the Lord. This is the covenant that I will make with the house of Israel after those days, says the Lord: I will put my laws into their minds, and write them on their hearts, and I will be their God, and they shall be my people. And they shall not teach every one his fellow or every one his brother, saying, ‘Know the Lord,’ for all shall know me, from the least of them to the greatest. For I will be merciful toward their iniquities, and I will remember their sins no more.” In speaking of a new covenant he treats the first as obsolete. And what is becoming obsolete and growing old is ready to vanish away. Now even the first covenant had regulations for worship and an earthly sanctuary."
This passage is from the book of Hebrews. It was written probably around the early 60's in the first century. The author (whose name we do not know) was explaining the details of how the New Covenant established by Christ was to replace the Old Covenant of Moses. Much of his writing is along the lines of "the Old had good things, but the New is better". The passage quoted above is one of those instances. He says, essentially, whatever the Old had, the New surpasses it. In other words, if the New Covenant was in any way inferior to the Old Covenant, his whole argument would be lost.
Those final words in the passage above: "even the first covenant..." have a powerful point to them that we might not notice. We sometimes take certain words for granted, and think little of their true weight. The little word "even" can easily be missed in that verse. "Even" connects two things together, but in a way that is more significant than if we merely said "also". It is like saying, "yes, this is true, but what is more shocking is that that is also true".
So when the author of Hebrews says "even the first covenant had regulations for worship and an earthly sanctuary", he is contrasting that "first covenant" (of Moses) with the "new covenant" (of the Catholic Church established by Jesus Christ) that he referred to earlier. It is as if he said "We all know, obviously, that the Church has regulations for worship and an earthly sanctuary, but it is just as true that the nation of Israel also had regulations for worship!" If the Church were not to have specific rules for the Mass, it would be inferior to the Old Covenant because no rules means chaos. He argues from the fact of the New Covenant having rules to the implication that the Old also did (not the other way around).
This might not seem to be shocking to us today; we see things differently. We all know that there were rules and regulations for the worship of the Old Testament temple. And, furthermore, we also know that the Church has rules and regulations today. There is nothing surprising about that. What is surprising is that the author is saying this in the middle of the first century. Long before modern Canon Law, or any of the current regulations for the Mass.
The point is, the author of Hebrews (whoever he was [not likely St. Paul as many claim]) was saying that there was already, in the first century, a set of regulations for the Mass. This means that while the Apostles were mostly still alive, they had already set standards and expectations for how to celebrate the Mass. Yet, (and here is the important part) these are not written anywhere in the New Testament. Even if we acknowledge (as most do) that the book of Revelation is laid out in the basic pattern of the Mass, it does not give rules like, "stand here, kneel here, read this" etc.
Where, then, are these sets of rules? Lo and behold! they are in the verbally communicated Tradition that the Apostles gave to the first Bishops of the Church, and then were handed down to subsequent generations. As Catholics we know this kind of thing happens, but we usually do not think much of the presumption of it that existed in the minds of the first Catholics who were learning directly from the Apostles. They virtually never mentioned it, because it happened all the time and everyone knew it. They did not have to prove it to anyone; it was already a reality, and the Apostles who were telling them these very things were still walking among them.
Wow! What would those rules have looked like? Though some certainly may have changed down through the centuries, history records that very few of them did. History records that the way they worshiped was guarded as an essential of what it means to perform the ceremonies of the Mass. Many of the Martyrs died to protect the Mass and to keep it secure and consistent with what the Apostles' said.
This is why our Mass must retain the forms of the past, and not seek "new innovations". For someone to try to come up with a brand new form of the Mass, completely disconnected from the historic manner given by the Apostles, would be to abandon the authoritative Traditions that we hold so dear. (No one would ever do that, would they???). That would be like ignoring the "regulations for worship" that the Apostles gave us. Let us guard the Mass, and not seek to "play games" with it. Let us constantly be asking ourselves, "are we faithful to the regulations for worship that were given to our forefathers?" And, let us always be willing to seek greater faithfulness in the worship of God.