The collect for this coming Sunday (Trinity 21 in the Prayer Book Calendar) was originally taken from the Gelasian Sacramentary.
GRANT, we beseech thee, merciful Lord, to thy faithful people pardon and peace, that they may be cleansed from all their sins, and serve thee with a quiet mind; through Jesus Christ our Lord. Amen.
The word "quiet" was changed from the original Latin which would have been translated "secure". Although we all want "secure" minds (cf. James 1:8), there is something about a "quiet" mind that is worthy of our attention. Those with a "secure" mind will usually also have a "quiet" mind, but not always. The two are related, but not equivalent. A quiet mind is that which is in submission to the admonition "be still and know that I am God" (Psalm 46:10).
What is the opposite of a "quiet" mind? A "noisy" mind is the obvious opposite; but what does it mean to have a noisy mind? When you are nervous about the future and begin to speculate (even silently) about the possible bad scenarios that you may encounter, you have a noisy mind. When you are talking with someone and you find your mind going back to a situation that occurred a few days ago so that you can replay it over and over, you have a noisy mind. When you neglect to fulfill your responsibilities (school, work, home, etc.) because you keep dwelling on the strained relationship you have with someone, you have a noisy mind. When you try to forget a sin you committed last month but cannot (even though you went to confession and did your penance), you have a noisy mind.
Although a noisy mind is never good in itself, sometimes it can be a useful tool to make us realize our spiritual state (like when you stub your toe on a big rock and it prevents you from falling flat on your face). Hence, we should not just try to silence the noise, but rather ask ourselves why our minds are noisy. It might not be because of anything in the immediate context of life, and thus we have to look deeper to discover how we got here. There are times when the noise of our minds has become such a habit that we have forgotten the reason why it is there, and it thus clouds our thinking even more. This should cause us to do more soul searching.
Notice that the collect connects "pardon" (originally "indulgence" in the Gelasian Sacramentary!) with "peace" as being those things that we petition the Lord to grant to His faithful people. Jesus is the Prince of Peace and He wants to enable us to be at peace with the Father as well as with each other; but He also wants us to be at peace within our individual selves. All sorts of challenges come at us from different fronts, but when our minds are clouded with noise and distractions, then those challenges can make peace seem like a friend who has been away on vacation for too long. Peace is available, always, through the meritorious work of our Lord Jesus, but that does not mean that we always find it as soon as we need it. He alone is able to give "peace", and yet at times we act as though we have forgotten this and seek it from other sources.
Here in Des Moines at St. Aidan's Church we have a "said-Mass" on Wednesday nights. With no music or chanting, there are a number of points where things are completely silent other than me moving around at the altar (and an occasional sniffle or cough from the pews). For some reason that I am not completely aware of, the ablutions seem to me to be much longer than they actually are. No one is left at the rail, my acolyte is doing some things over by the credence, and I am focused on my liturgical duties. The people, having returned to their seats are silently saying their prayers and waiting for me to finish.
Occasionally, there is the nagging feeling in my gut that I should hurry it up so that we can get on with the liturgy, but I know better. That nagging feeling is wrong. The time after communion is important for prayer and reflection. It should be allowed to go slowly and never be rushed (just like communion itself). It is this "holy silence" that we (especially us modern westerners) need to seek to take full advantage of. Those said-Masses provide a time of silence after communion that is vital to our spiritual growth (and on Sundays when we have a communion hymn–though beautiful–it is actually a bit of a hindrance to this). The people who skip a said-Mass because "it's too quiet without the music" are actually missing something quite important. Learning how to benefit from times of silence is not something that we do merely to fill in that time after communion; it is something that helps to enable us to serve God better.
We are told in Zechariah 2:13 to "Be silent, O all flesh, before the LORD". Where, in this life, are we more "before the Lord" than right after communion? Do you allow yourself to be distracted during that time (and, no, I am not referring to things you cannot control) or do you make an effort to be quiet and silent before the Lord so that your heart and mind can practice being at peace? Although some of us will want to fill that time of silence with prayers, that is not necessarily the best spiritual discipline to seek. Yes, those who get out their shopping list to add something, or those who think about what they are going to do when they get home are wrong. Pray, yes, but then just be silent. Do not try to fill that time with anything other than silent submission to the Lord. I recall someone once saying something that took a long time for me to learn. I was told, "you know how to talk real well, but you need to learn how to shut up also." That was some of the best advice I ever received. When I learned how to "shut up" and listen, I also learned how to be quiet and silent before the Lord. That made me able to do this at other important times in life when a silent mind was desperately needed.
Therefore, ask yourself what is on your horizon? Are there things coming up ahead that will require a quiet mind? Are you preparing yourself, even now, to be ready to deal with those things? There are priests who are nervous about their status with the Ordinariates; "will I get my nulla osta?", "will I get a rescript?" "will I have to go through further education?" There are laymen who are anxious about whether their new group will become a full parish in the Ordinariate. There are people who are fretting about whether the Ordinariates will succeed at all. How are you going to handle these (or many other) concerns? Will it be with a noisy mind or a quiet mind?
Pardon and peace allow us to deal with life with a clear mind. Then we are able to confess our sins to God properly and find absolution and make restitution. Only after this can we achieve that state of mind wherein we can serve God to the fullest extent; not clouded by our own thoughts, or confused by the jumble of worries. There are many things that will help us in this endeavor, but practiced silence is one of the most significant. Learn to be "silent before the Lord" when you are in His presence. It will become easier, and it will help you to serve Him with gladness and joy. This is what it means to "be still"; this is what it means to serve Him "with a quiet mind".