The Collect, Secret and Postcommunion (as well as the Preface, which we have already considered) are not strictly part of the Ordinary of the Mass. However these prayers in the Roman Rite (particularly the Collect) tend to follow a fairly strict pattern, and although I obviously cannot deal with all of them (there are literally hundreds still in use, and even these are only a fraction of the total number composed over the centuries), I think it is worth while explaining this pattern, because it will help you, with the assistance of the English translation in your missal, to understand them.
Many of the Collects in the Old Roman Rite are to be found in the Gregorian Sacramentary, which reflects the revision of the rite by St. Gregory the Great around 600 AD. This sacramentary contains about 900 Collects, of which approximately 650 appear in other liturgical books of the period. At one time it was thought that all the remainder were composed by St. Gregory personally. However, a Benedictine monk named Henry Ashworth undertook the mammoth task of trawling through all the surviving writings of St. Gregory to identify verbal similarities with the Collects of the Gregorian Sacramentary, and thereby establish which of the Collects could be attributed with reasonable certainty to him. He detected such similarities in about 80 cases. It doesn’t of course follow that these are the only Collects composed by St. Gregory, because he might have composed others which do not happen to contain expressions found in his other writings. However that may be, it seems certain that the vast majority of the Collects in the sacramentary were already in use by 600 AD. Quite a few of them have survived in the new missal of Paul VI, though often in different contexts and partially rewritten to reflect different theological perceptions.
Roman Collects have a basic quadripartite pattern. Firstly, God is invoked, sometimes simply as “Deus” or “Dómine”, but frequently at somewhat greater length as for example “Omnípotens sempitérne Deus” or “Omnípotens et miséricors Deus”. This is followed by a relative clause which describes some attribute of God or some action of His which is relevant to the petition which immediately follows. Then comes a petition for some grace or favour, spiritual or temporal, introduced by a phrase such as “da, quaésumus” or “concéde propítius”. This third section often, though not always, falls into two subsections, the first being the request, the second the reason why we are making it, or the effect we hope the granting of our request will have on us. The prayer concludes with a doxology, in one of a fixed number of standard patterns.
Let us take as an example the Collect for the feast of Corpus Christi (composed by St. Thomas Aquinas). The doxology is the one appropriate for Collects addressed to Our Lord rather than to God the Father. I have numbered the sections so that the pattern stands out clearly.
1. Deus,
2. qui nobis sub Sacraménto mirábili
passiónis tuae memóriam reliquísti:
3a. tríbue, quaésumus, ita nos Córporis et Sánguinis tui sacra mystéria
venerári,
3b. ut redémptionis tuae fructum in nobis iúgiter sentiámus
4. Qui vivis et regnas cum Deo Patre, in unitáte Spíritus Sancti, Deus per
ómnia saécula saeculórum. Amen.
This translates as:
1. God,
2. Who hast left to us under a wonderful Sacrament a memorial of Thy Passion
3a. grant, we beseech [Thee], that we may in such manner venerate the holy mysteries of thy Body and Blood,
3b. that we may constantly feel the fruit of Thy redemption within us
4. Who livest and reignest with God the Father, in the unity of the Holy Spirit, God through all the ages of ages. Amen.
Incidentally there are no less than three examples in this Collect of something which we have met before, a genitive coming before the noun to which it relates, namely “passiónis tuae memóriam”, “Córporis et Sánguinis tui sacra mystéria”, and “redémptionis tuae fructum”.
A variation on the above pattern, which is quite common, is to omit the second section entirely and to place the invocation of God after the introductory words of the third section. The Collect for the third Mass of Christmas Day, for instance, reads “Concéde, quaésumus, omnípotens Deus, ut nos Unigéniti tui nova per carnem Natívitas líberet, quos sub peccáti iuga vetústa sérvitus tenet” (“Grant, we beseech [Thee], almighty God, that the new birth of Thine only-begotten Son in the flesh may free us, whom the old servitude holds beneath the yoke of sin”). The same pattern is found in the second Mass of Christmas and in the Mass for Ascension Day, to name but two of many other instances. Since the Collect quoted is addressed to God the Father, the doxology which concludes it is of course different from that for the Collect of Corpus Christi: “Per eúndem Dóminum nostrum Jesum Christum Fílium tuum, qui tecum vivit et regnat in unitáte Spíritus sancti, per ómnia saécula saeculórum. Amen”.
One of the best known Collects in the missal is that for Whit Sunday, which is frequently used, in translation, as a prayer for the guidance of the Holy Spirit. Here it is, analysed into its component parts:
A rather literal translation would be:
“Hodiérna die” is a rather rhetorical alternative for the more usual “hódie”, which we find for example in the Pater Noster, (though “hódie”is actually a contraction of “hodiérna die”). Note too that Latin says “to know right [things]” and “to rejoice from His consolation”. You will also have noticed that in this collect the third section is not divided into two subsections, because the reason for our request is effectively contained in the request itself, and does not need any further explanation. The Collect is addressed to God the Father and the doxology is similar to that for the third Mass of Christmas Day, but since it is the Holy Spirit and not Our Lord who is mentioned in the prayer, we say “the same Holy Spirit” rather than “the same Jesus Christ Our Lord”.
You can now go back to the prayer which the priest says in blessing the drop of water which he adds to the wine in the chalice at the Offertory, and see how it fits this pattern:
I have bracketed the words “per huius aquae et vini mystérium” because these were added later to turn this ancient Christmas Collect into a prayer accompanying the blessing of the water. And I’m sure you won’t have failed to spot two more examples of the “genitive before noun” word order, namely “humánae substántiae dignitátem” and “huius aquae et vini mystérium”, in the latter instance actually separating the preposition “per” from the noun to which it relates, as it did in St. Gregory’s Christmas Preface (“per incarnáti Verbi mystérium”).
The Secret Prayer which concludes the Offertory (or the Prayer over the Gifts, as it was known in the old Roman sacramentaries, and again in the Novus Ordo), is less structured than the Collect. It consists in a request for the acceptance of the gifts which we offer, so that we may obtain certain specified spiritual favours. It is usually very short, and ends with one of the standard doxologies. It is normally introduced by some sort of expression as “Súscipe, quaésumus, Dómine” (“Receive, we beseech Thee, O Lord”) or “Áccipe, quaésumus, Dómine” (“Accept,” etc.) or “Concéde, quaésumus, Dómine” (“Grant,” etc.). The sacrificial gifts are often referred to as “obláta múnera” (“offered gifts”), sometimes shortened in a typically Latin way to simply “obláta”. Other words which you will frequently find are “offérimus” (“we offer”), “sanctífica” (“sanctify”), “oblátio” (“offering”), “dona” (“gifts”), “hóstia” or “sacrifícium” (both meaning “sacrifice” or “offering”). The last named word, in the plural, is frequently joined to “praesénta”, to mean “presented offerings”, for example in the Secrets for the fourth Sunday of Advent and the first Thursday, second Sunday, third Thursday and fourth Sunday in Lent.
Here is the Secret for the fifth Sunday after Easter: “Súscipe, Dómine, fidélium preces cum oblátionibus hostiárum, et per haec pia devotiónis offícia, ad caeléstem glóriam transeámus” This translates as: “Receive, Lord, the prayers of the faithful with [our] sacrificial gifts, and through these dutiful services of [our] devotion, may we pass on to heavenly glory”. “Oblátionibus hostiárum”, which I have translated as “sacrificial gifts”, literally means “offerings of sacrifices”. You will find it more than once in the Missal, for example in the Secret for the fourth Wednesday in Lent.
Sometimes the Secret makes reference to the feast which we are celebrating in the Mass of the day, particularly on the more important feasts, but more often than not it is a general prayer which could be used on any day of the year. As an example of the specialised Secret we may quote that for Whit Sunday: “Múnera, quaésumus, Dómine, obláta sanctífica, et corda nostra Spíritus illustratióne emúnda”. The language of this Secret is closely related to that of the Collect for the same day; the only word which you have not already met is “emúnda”, which is an imperative from “emúndare”. It is a stronger word than “múndare”, meaning “thoroughly cleanse”, rather than just “cleanse”. Note that the expression “obláta múnera” is not only reversed but also divided by the words “quaésumus, Dómine”; this is a good example of the flexibility which Latin has, as an inflected language, to vary the word order for stylistic reasons without affecting the sense.
The Postcommunion, as the name implies, is a prayer that God may grant us the fruits of the Sacrament which we have just received. Like the Secret, it is normally expressed in very general terms, but sometimes on major feasts it will contain a reference to the feast being celebrated. Like both the Collect and the Secret, it always concludes with one of the standard doxologies. The benefits which we pray for may be expressed in spiritual or temporal terms or indeed both. Consider, for example, the Postcommunion for the third Sunday after Easter: “Sacraménta quae súmpsimus, quaésumus, Dómine, et spirituálibus nos instáurent aliméntis, et corporálibus tueántur auxíliis” (“May the sacraments which we have received, we beseech [Thee], Lord, restore us with spiritual food, and protect us with physical help”).
For the Mass of Easter Sunday, there is, as we would expect, a reference to the feast; “Spíritum nobis, Dómine, tuae caritátis infúnde, ut, quos sacraméntis paschálibus satiásti, tua fácias pietáte concórdes” (“Pour into us, Lord the spirit of Thy love, so that [those] whom Thou hast satisfied with [Thy] Paschal sacraments Thou mayest make through thy goodness one in harmony”). Most of the other major feasts (with some exceptions, such as the Ascension) have these individual Postcommunions. The generalised Secrets and Postcommunions can in theory be used on any day, and in the old sacramentaries many of them are found on quite different days from those for which they are prescribed in the Missal of St. Pius V.
All the ancient sacramentaries contain a further prayer, known as the “Orátio super Pópulum” (“Prayer over the People”), which was a sort of second Postcommunion, said immediately after the first. It eventually went out of fashion, except on the weekdays of Lent, where it survived in the Missal of St. Pius V. The post-Vatican II liturgical reformers abolished it completely, which was an odd thing to do in view of their claim that one of their principal objectives was to restore to the liturgy ancient elements which had fallen out of use during the Middle Ages.