I appeal to you therefore, brethren, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship. Do not be conformed to this world but be transformed by the renewal of your mind, that you may prove what is the will of God, what is good and acceptable and perfect (Romans 12:1-2).
This amazing passage (I encourage you, read it over; a couple times; slowly) is an appeal by St. Paul to the Christians of the first century to be changed; not by the world, but by the Mass. Notice he is speaking about us offering ourselves as sacrifices (a key part of the Mass) and makes it clear that he is speaking about the context of worship.
He tells them (and us) that we must be actively involved in the Mass in such a way that it transforms us (from sinful, foolish people, into holy, wise people) so that we can know what is right. It is essentially a promise. St. Paul promises that if we allow the Mass to convert us more and more unto the Lord every time we attend, then we will become spiritual geniuses! (Which also promises that if we do not allow it to convert us, then we will become spiritually fooish--just consider the ramifications of this.)
This presumes three things. First, it presumes that you are attending Mass (and not just once in a while, but at least the bare minimum, and preferably more than that). Second, it presumes that when you are in the Mass, that you are engaged in such a way that you go away changed. Maybe the change will be small one time, and larger the next, but there will always be some kind of "transformation" of who you are into someone more godly. Third, it presumes that the Mass you attend is being done reverently and obediently because he is concerned that what we do be "acceptable to God" (in other words, if we do it wrongly, He may very well not accept it!).
So here is the thought for today: Stop trying to change the Mass, and let it change you!