100   Formation, The Catholic Priesthood and The Modern Age 

 

 

 

C H A P T E R  7  

 

 

 

Liturgical Formation In Seminaries: 

 A Lesson From Lex Orandi, Lex Credendi 
 

Anthony Olumuyiwa OMODUNBI 

 

 

 

Introduction 

Few weeks after my ordination to the Catholic priesthood, the diocese 

of my incardination (Osogbo diocese) organised an orientation 

program for all the new priests to be involved in pastoral engagement 

within the diocese. The priest who anchored the liturgy session 

opened by saying: “you have to put aside what you have been taught 

in the seminary and learn how we do things in the diocese.” My first 

intuitive reaction was, why then do we have to spend nine years in the 

seminary if it is only to be ordained and put aside what we have 

learnt? He went further to say, “you have learnt theory in seminary 

and now you will be involved in the practical life of the liturgy.” I 

was a bit settled at that and was disposed to go through the orientation 

exercise which was however highly beneficial for my integration into 

the pastoral life in the diocese.  However, after ten years of pastoral 

ministry and deeper studies in the liturgy, the question continues to 

pop up querying why the gap between theory and practice in seminary 

formation? Why what should was learned in seminary not adequately 

and sufficiently introduce the newly ordained into the ministry? Or in 

this particular case, why should what was learnt in seminary not be 

the ‘moulding of a liturgical minister?’  

While I do not want to engage in the argument whether 

priestly formation, especially in Nigeria, is achieving the goal of 

moulding liturgical minister to meet the present-day challenges or not, 

this reflection seeks to emphasise that all that is being taught and done 



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in seminary, especially in the areas of moral, spiritual and 

intellectual/academic formation, should at the same time have a 

liturgical focus. While this does not imply that formation should be 

reduced to liturgy, this reflection argues that prioritizing the liturgical 

dimension of priestly formation is one of the major ways of bridging 

the supposed gap between theory and practice. After all, ‘the liturgy is 

the summit towards which the activity of the church is directed; it is 

also the source from which all its power flows.1 It is through the 

liturgy that the work of our redemption takes place;2 it is rightly seen 

as an exercise of the priestly office of Jesus Christ and therefore, ‘no 

other action of the Church equals its effectiveness by the same title 

nor to the same degree.’3 Thus, having seminary formation with a 

liturgical focus can never be overemphasised. 

To justify the position of this reflection, I will consider the 

meaning of the age-old maxim lex orandi, lex credendi as it pertains 

to the indispensable role of liturgy in the life and faith of the Church, 

and how it could effectively bridge the gap between worship and 

doctrine, theology and liturgy, and theory and practice. 

 

Lex Orandi, Lex Credendi: A Maxim In Context 

The late 20th-century discussion on the emergence of what is today 

called liturgical theology, brought with it a new look at the age-old 

Latin maxim, lex orandi, lex credendi. The discussion which centres 

around the relationship between liturgy and theology reopened the 

understanding of the maxim lex orandi, lex credendi as it sheds light 

on the interplay between praying and believing, between Christian 

worship and doctrine.4 Major scholars in the discussion affirm the 

importance of liturgy in the understanding of the belief of the Church 

since she prays as she believes. This, however, does not mean that 

what the Church believes does not affect how the Church prays, as it 

is evident in the periods of reforms. The proper understanding of the 

context in which the maxim first appeared is therefore instructive on 

how it should be correctly understood and used. 

The axiom lex orandi, lex credendi is the binominal for the 

phrase ‘ut legem credendi lex statuat supplicandi’ that is ‘so that the 

law of prayer may establish a law for belief.’  The phrase has its root 



102   Formation, The Catholic Priesthood and The Modern Age 

in the response attributed to a lay monk, Prosper of Aquitaine (a 

disciple of Augustine), to Semi-Pelagians.5 Like Augustine, Prosper 

of Aquitaine argues in favour of the need of God’s grace for the 

salvation of human beings. For Prosper, the grace of God is needed at 

different instances and in different degrees in one’s life. To justify his 

position, Prosper argues from the scripture, Church tradition and the 

liturgy of the Church: 

In inviolable decrees of the blessed apostolic see, our 

fathers have cast down the pride of the pestiferous 

novelty and taught us to ascribe to the grace of Christ 

the very beginning of goodwill, the growth of the 

noble efforts, and the perseverance in them to the end. 

In addition, let us look at the sacred testimony of 

priestly intercessions which have been transmitted 

from apostles and which are uniformly celebrated 

throughout the world and in every catholic church; so 

that the law of prayer may establish a law for belief. 

For when the president of the holy congregations 

perform their duties, they plead the cause of the 

human race before the divine clemency and, joined in 

the sighs of the whole Church, they beg and pray that 

grace may be given to unbelievers; that idolaters may 

be freed from the errors of their impiety; that the Jews 

may have the veiled removed from their hearts and 

that the light of truth may shine on them; that heretics 

may recover through acceptance of the faith; that 

schismatics may receive afresh the spirit of charity; 

that the lapsed may be granted remedy of penitence; 

and finally that the catechumens may be brought to 

the sacrament of regeneration and have the court of 

the heavenly mercy opened to them. 

That these things are not asked of the Lord lightly or 

uselessly is shown by the outcome.  For God is 

pleased to draw many out of every kind of error, 

liberating them from the power of darkness and 

placing them in the kingdom of his beloved Son, 

turning them from the vessel of wrath to vessels of 

mercy.  This is felt to be so completely the work of 

God that the God who achieves it is always given 



Liturgical Formation In Seminaries: A Lesson From...      103 

 

 

thanks and praise for bringing such people to the light 

or truth.6 

There is need to underscore some points from this citation in order to 

get its relevance to this reflection. 

First, what Prosper refers to as the practice of prayer covers 

for all of the liturgy and not just a reference to liturgical texts. In the 

following chapters of his work, he advanced the same argument in 

relation to ritual actions like pre-baptismal exorcism and exsufflation 

(symbolic action of blowing out the spirit) to argue that they are 

actions referring to the fact that there is need for the grace of God 

even for infants who are brought forward for baptism. 

Second, Prosper acknowledges that liturgy is not the only 

doctrinal source, nor lays claim that it is the primary source.7 On the 

contrary, liturgy, together with the magisterium and scriptures are 

sources for doctrine. Hence, he used the words ‘in addition.’ In the 

mind of Prosper, none is considered as receiving its authority from the 

other. Rather, they all corroborate one another. At best, what we can 

say is that the agreement between the sources further fosters their 

authority. In fact, in its context, Prosper in his mind simply implies 

that ‘one may have recourse to the prayers of the Church in order to 

resolve the controversy on grace because they correspond to a biblical 

mandate (1 Tim 2:1-2), and are the expressions of the living tradition 

of the Church.’8 In other words, ‘Church’s engagement in rites 

grounds the articulation of Church’s belief’9 in as much as it aligns 

with the scriptures and magisterium. 

Third, the writing of Prosper affirms the authority of the 

liturgy in the facts that it is a universal prayer, the same everywhere 

and followed by all Catholics all over the world. They are credible 

because, they are actions of the holy congregation in the presence of 

God, and the fact that God answers the prayers attests to its authority. 

 

Lex Orandi, Lex Credendi: A Principle in Practice 

Though the adage, ‘ut legem credendi lex statuat supplicandi’ often 

reduced to lex orandi, lex credendi is attributed to Prosper of 

Aquitaine, the fundamental principle underlying the adage predates 

Prosper’s formulation.  The principle is evident in many New 



104   Formation, The Catholic Priesthood and The Modern Age 

Testament writings and was carried on by the Apostolic Fathers.  As 

an example, the prayers addressed to Jesus in the New Testament 

Christological hymn (Philippians 2: 5-11), confessing Jesus as the 

Lord – sharing the divine name KYRIOS used for YHWH – 

contribute immensely to the doctrine of the Divinity of Jesus.  In the 

same way, the Trinitarian baptismal practice in the Matthean 

community reflected in Matthew 28:19 reflects an instance where the 

practice of the Church is already constituting in a way the belief of the 

Church in the Trinity. 

Many of the early Church Fathers constantly had recourse to 

the liturgy in the explanation of the faith of the Church.10 Ignatius of 

Antioch drew from the Eucharistic liturgy to argue against the 

Docetists (who claim that the human body of Jesus is unreal but a 

phantasm, and therefore cannot really experience suffering). Thus, 

Ignatius refutes the Docetists that their teaching negates the truth of 

the Eucharist as the flesh of the Jesus Christ our saviour who suffered 

for our sins and was raised from the dead.11 

Through several references to the liturgy of baptism, early 

Church writers argue for what developed to the different doctrines 

related to baptism. For instance, in the argument against Julian 

Eclanum, who teaches that children are born without original sin, 

Augustine argues from the implication of exorcism and exsufflation 

which are carried out during the baptism of Children. For Augustine, 

the two rites – exorcism and exsufflation – are done to release the 

children from the power of the devil. And that it is because there is an 

ailment that we have recourse to the remedy. This same approach of 

appealing to the liturgy to understand the belief of the Church about 

baptism is also evident in the post-baptismal mystagogical catechesis 

of Ambrose of Milan, Cyril of Jerusalem and Theodore of 

Mopsuestia.12 These bishops taught the neophytes what they are to 

believe based on what was celebrated.  

In the sixteenth century, the axiom witnessed a modification in 

its application. During the period of the Reformation, the disputes in 

the understanding of Christian doctrines led to the reformulation of 

liturgical texts and practices. For the reformers, what is believed is 

what should reflect in worship. Believing now modifies and 

establishes praying. It should be noted that this move is not a denial, 

but a reversal, of the maxim. The principle of lex orandi, lex credendi 



Liturgical Formation In Seminaries: A Lesson From...      105 

 

 

was not absent but understood in a different way. A way that affirms 

the dual movement of the influence of one on the other. 

The reversal approach to the principle is also well favoured in 

the reform of the Roman Catholic liturgy. In his encyclical on the 

liturgy, Mediator Dei, Pope Pius XII modified the meaning of the 

maxim in this succinct statement:  

during the discussion of a doubtful or controversial 

truth, the Church and the Holy Fathers have not failed 

to look to the age-old and age-honored sacred rites for 

enlightenment. Hence the well-known and venerable 

maxim, "Legem credendi lex statuat supplicandi" - let 

the rule for prayer determine the rule of belief. The 

sacred liturgy, consequently, does not decide or 

determine independently and of itself what is of 

Catholic faith. More properly, since the liturgy is also 

a profession of eternal truths, and subject, as such, to 

the supreme teaching authority of the Church, it can 

supply proofs and testimony, quite clearly, of no little 

value, towards the determination of a particular point 

of Christian doctrine. But if one desires to 

differentiate and describe the relationship between 

faith and the sacred liturgy in absolute and general 

terms, it is perfectly correct to say, "Lex credendi 

legem statuat supplicandi" - let the rule of belief 

determine the rule of prayer.13  

 

Pope Pius XII acknowledges the symbiotic interplay between faith and 

liturgy and throws more weight behind the rule of faith determining 

the rule of prayer.  He justifies this claim on the ground that the 

ecclesiastical authority has the responsibility of organizing and 

regulating divine worship, ‘enriching it constantly with new splendour 

and beauty, to the glory of God and the spiritual profit of Christians’ 

(MD no.49). The ecclesiastical authority carries out this responsibility 

by modifying the human elements of the liturgy as the needs of the 

age, circumstance and the good of souls may require, and as the 

ecclesiastical hierarchy, under the guidance of the Holy Spirit, may 



106   Formation, The Catholic Priesthood and The Modern Age 

have authorized (MD no.50). While the reasons are laudable and 

appealing, it does not necessarily warrant the reversal of the meaning 

of the maxim.14  

In a nutshell, either understood in its original context or in the 

application of the reversal, the axiom, lex orandi, lex credendi 

expresses a deep and mutual relationship between liturgy and the faith 

of the Church. The liturgy celebrates the faith of the Church. This is 

where the maxim is relevant to the core of this reflection. The 

relevance is that if all that is learned in the seminary is to aid in the 

understanding of the faith and life of the Church, and for the future 

priest to be equipped for the ministry, what is learned invariably 

affects how future priests would understand and relate with the liturgy, 

which is the source and summit of the life of the Church. Therefore, 

for seminary formation in faith and ministry to achieve its goal, the 

approach to liturgical formation is key. 

 

Reconsidering the Liturgical formation in Seminaries 

The Vatican II Decree on the Training of Priests, Optatam Totius (OT) 

recognizes that the training of priests should ultimately have a 

liturgical focus. Making the clarion call towards this recognition, the 

conciliar fathers requested that the entire formation of major 

seminarians should aim at enabling students to be formed as pastors of 

souls, following the example of Jesus our teacher, priest and shepherd. 

(OT no.4).  Such formation is described as having a liturgical focus 

when the conciliar fathers say that ‘the students are to be trained for 

the ministry of the word... for the ministry of worship and 

sanctification so that by prayer and sharing in the liturgical 

celebrations, they may carry on the work of salvation’ (OT no.4). 

While the document makes the suggestion of the various necessary 

courses to be undertaken in the seminary to achieve the goal of the 

formation, the document made two other salient points relevant for 

this reflection. 

Firstly, in the revision of the ecclesiastical studies to be 

undertaken, the primary aim is to coordinate philosophy and theology 

in such a way that together they open the minds of the students more 

and more to the mystery of Christ, which touches the whole of human 

history, continually influencing the Church, and is particularly at work 

in the priestly ministry (OT no.14). The mystery of Christ which 

contains, but not limited to, the work of our redemption takes place 



Liturgical Formation In Seminaries: A Lesson From...      107 

 

 

through and in the liturgy (SC no. 2). It is this same celebration of the 

liturgy that all of the ecclesiastical studies in seminary formation is 

revised to enhance in the life of seminarians. 

Secondly, when the document OT outlines the various 

disciplines that should be included and their respective relevance to 

the formation of seminarians, Liturgy was accorded a distinct position 

- not just one of the disciplines but the focus of all. To underscore this 

position, OT simply says that ‘Liturgy which is to be regarded as the 

first and ever necessary source of true Christian spirit, should be 

taught in the spirit of articles 15 and 16 of the constitution on the 

Sacred Liturgy’. (OT 16). It is pertinent at this juncture to look at the 

content of the articles of Sacrosanctum Concilium referred to:  

15. Professors who are appointed to teach liturgy in 

seminaries, religious houses of studies, and 

theological faculties must be properly trained for their 

work in institutes specifically designed for this 

purpose. 

16. Sacred Liturgy is to be ranked among the 

compulsory and major causes in seminaries and 

religious houses of studies. In theological faculties, it 

is to be one of the principal courses. It is to be taught 

under the theological, historical, spiritual, pastoral, 

and juridical aspects.  In addition, those who teach 

other subjects, especially dogmatic theology, sacred 

scripture, spiritual and pastoral theology, should – 

while accepting the intrinsic demands of their own 

disciplines – expound the mystery of Christ and the 

history of salvation in a manner that will make clear 

the connection between their subjects and the liturgy, 

and the unity of all priestly training. 

 

The request of SC 16 is of great significance which, I strongly believe, 

its neglect is partly one of the reasons for that gap between theory and 

practice, what is taught in the seminary and what is practised. All the 

subjects are expected to shed light, no matter how little, on the 

understanding and celebrations of the mystery of Christ. Courses that 



108   Formation, The Catholic Priesthood and The Modern Age 

seem highly unrelated in any way to the liturgy in the past has proven 

to be of great importance in the understanding and appreciation of the 

mystery being celebrated. For example, different developments in 

social sciences – sociology, psychology and anthropology have really 

developed ritual studies which today offers avenues for better 

understanding of Christian worship and specifically sacramental 

theology and practice.  

The demands from the teachers of different courses in the 

seminary further calls for the reassessment of their process of 

recruitment. Pope Francis was conscious of this need when he writes 

that those who teach in the ecclesiastical faculties must be 

distinguished by a wealth of knowledge, witness to Christian and 

ecclesial life, and sense of responsibility.15 Though the intrinsic 

demands of some of these disciplines may not necessarily involve 

relating it to Christian worship, students are to be prepared in such a 

way that they have the love of rigorous investigation, observation and 

demonstration of truth, together with an honest awareness of the limits 

of human knowledge (OT 15).  This will enable them to be better 

disposed and appropriate whatever is taught in relation to Christian 

worship. 

Moreover, while many of the courses may not directly be 

related to worship, they could be related to faith and the understanding 

of human person. In these ways, the courses bolster the preparation of 

seminarians for liturgy in two ways. On the one hand, since the 

Church celebrates what she believes, relation of courses to faith 

invariably fosters conviction and understanding in worship.  On the 

other hand, the human person is the primary subject of worship. A 

better understanding and appreciation of the human person, therefore, 

enhance the liturgical ministry of the priest.  

Furthermore, to corroborate the importance of liturgy at the 

core of priestly formation, the conciliar fathers suggested that the 

spiritual formation of students in seminaries and religious houses 

should be given a liturgical orientation (SC no.17). This is purposely 

to aid their understanding of the sacred rites and to assist them to 

participate in them wholeheartedly. In this same vein, the seminarians 

are equipped to celebrate sacred mysteries and popular devotion with 

the spirit of the sacred liturgy (SC no.17). 

 

 



Liturgical Formation In Seminaries: A Lesson From...      109 

 

 

Forming Priests as Christ-like Leitourgos 

Seminary formation is geared towards making students like Christ - 

teacher, priest and shepherd. This expectation of the conciliar fathers 

is further expressed in the Decree on the Ministry and Life of Priest, 

Presbyterorum Ordinis (PO) that the sacrament of orders make priests 

in the image of Christ (PO no.12). This fundamental notion of 

Catholic priesthood has its effect on how priests are formed. The 

introduction to the Ratio Fundamentalis Institutionis Sacerdotalis 

expressly stated that ‘the purpose of priestly education/formation is 

based on the concept of the Catholic priesthood.16 While the concept 

of Catholic priesthood may take volumes of writings to exhaust, I will 

want to discuss it in this reflection in relation to the foregoing 

argument of the priest being in the likeness of Christ. Or better put in 

the light of the understanding of the Catholic priest acting in persona 

Christi at liturgy. 

The New Testament highlights the priestly role of Jesus in 

different ways. He is regarded as the great high priest of the order of 

Melchizedek who offers both requests and supplications to God 

(Hebrew 5:5-7). He is our high priest who sits at the right hand of God 

ministering (leitourgos) in the heavenly sanctuary (Heb. 8:1-2). It is 

pertinent to note here that the author of the letter to the Hebrews refers 

to Jesus as our ‘liturgist.’ Contrary to the long-held opinion that 

liturgy is from the two Latin words laos (people) and ergon (work) 

resulting in the definition of liturgy as work of the people, Paul 

Marshal rightly corrected17 that it is from the words ergon (work) and 

leitos (public). Therefore, the etymological meaning of liturgy is a 

public work done on behalf of the people. It is in this light that we can 

better understand the priest as the minister of the word and the 

mystery of Christ as related in the Vatican II documents earlier cited. 

Seminary formation which intends to mould ministers like 

Christ, our liturgist, invariably aims at forming ‘liturgists.’ It is a 

disservice to the generations of believers who will be led in worship 

by him who does not understand what he is doing. In as much as the 

actions of the priests are to be carried out in the person of Christ, 

anything less than a formation after a Christ-like liturgist is a sham. 

Knowing rightly that the liturgy is the exercise of the priestly office of 



110   Formation, The Catholic Priesthood and The Modern Age 

Jesus Christ, his ministers are to be formed with the same ideal in 

mind. It will never be overemphasised that having a liturgical focus is 

the real essence of priestly formation. 

The centrality of liturgy in the formation of a priest does not 

end at his ordination. The conciliar fathers recommend ongoing 

liturgical formation for priests. This is intended to deepen their 

understanding of the mysteries they celebrate and to faithfully live the 

liturgical life (SC18).  This is essential so that remaining alter 

Christus, they at the same time remain a ‘liturgist’ who ministers in 

the name of Christ. 

 

Conclusion 
The maxim lex orandi, lex credendi was discussed in this reflection as 

highlighting the relationship between liturgy and theology, praying 

and believing, faith and worship. Since in the original usage of the 

maxim, liturgy, in agreement with scripture and tradition, influences 

what the Church believes, it is expedient that the formation of 

liturgical ministers put into consideration the urgent need of 

appropriating learning in the seminaries to have a liturgical undertone. 

The understanding of the maxim in its context affirms that the faith of 

the Church is what the liturgy celebrates. This affirmation guides 

against two extremes - of liturgical archaism (the idea that the way 

things are done in the past is always and the only ideal way of 

worship) and of the fluid liturgy (the idea that liturgy must adapt to 

modern-day ‘beliefs’ and its charismatic expressions). The faith of the 

Church which is celebrated in the liturgy is not a view or an ideology 

of a movement, no matter how popular within the Church. Therefore, 

the envisaged liturgical formation of seminarians prepares against the 

tendency of bringing different aberrations into worship and at the 

same time guards against rubricism.  

Perhaps, if what this paper has discussed is faithfully 

considered, the attitude of ministers to the liturgy may be more 

positive and their conviction in the power of the rites further 

strengthened. These will possibly help to bridge the supposed gap 

between what they are taught in the seminary and what is expected of 

them at worship. 

 

 

 



Liturgical Formation In Seminaries: A Lesson From...      111 

 

 

 Endnotes 
 
                                                           
1 Vatican Council II, Constitution on the Sacred Liturgy, Sacrosanctum 

Concilium, no. 10. (Henceforth referred to as SC). 
2 Sacrosanctum Concilium, no. 2. 
3 Sacrosanctum Concilium, no. 7. 
4 For a detailed discussion on the interplay between theology and liturgy, see 

Michael Aune, ‘Liturgy and Theology: Rethinking the Relationship,’ Worship 

81(2007): 46-68, 141-169. 
5 Pelagianism is the theological position that human beings, are like Adam 

before the fall. They are born innocent, with absolute free will and absolutely 

capable of obeying God’s commandment and by so doing merit eternal life on 

their own.  It was an extreme position against the Gnostic and Manichean 

doctrine. Augustine responding to the adherents of Pelagianism argues that 

human will is not free but sick, human nature is mortally wounded by sin and 

that from the moment of birth, human beings does not have the capacity to 

choose the good. This led to the development of Augustine’s teaching on 

original sin.  For him, it is only the grace of God that can enable human beings 

to turn to God. Without this grace, humanity is condemned.  Pelagianism was 

condemned at the Synod of Carthage in 418 and the Council of Ephesus in 431.  

However, there arose a slight modification of the teaching of Augustine to 

further emphasise the fact that God created man good and all about the goodness 

is not lost in the fall, giving rise to Semi-Pelagianism.  This doctrine holds on to 

the necessity of divine grace for salvation, but further claims that even the first 

step to this is dependent on free will. For further readings on Pelagianism and 

Semi-Pelagianism, See Jaroslav Pelikan, The Christian Tradition: A History of 

the Development of Doctrine, vol.1: The Emergence of Catholic Tradition (100-

600) (Chicago: University of Chicago Press, 1971), 278-331. 
6 Capitula Coestini 8. As translated by Geoffrey Wainwright, Doxology: The 

Praise of God in Worship, Doctrine and Life (New York: Oxford University 

Press 1980), 225-226. 
7 Some contemporary theologians however see in the maxim a confirmation of 

liturgy as the primary theology. Aidan Kavanagh, for instance, argues that the 

liturgy is the primary source for theology. See Aidan Kavanagh, On Liturgical 

Theology (New York: Pueblo, 1984), 134; Aidan Kavanagh, ‘Response: Primary 

Theology and Liturgical Acts’ Worship (1983): 323-324. 
8 Paul De Clerk, “‘Lex Orandi, Lex Credendi’: The Original Sense and 

Historical Avaters of an Equivocal Age,” Studia Liturgica 24 (1994): 192. 
9 Kevin W. Irwin, “Lex Orandi, Lex Credendi – Origins and Meaning: State of 

the Question” Liturgical Ministry 11 (2002): 59. 



112   Formation, The Catholic Priesthood and The Modern Age 

                                                                                                                                  
10 For elaborate discussion on the application of the principle in early 

christianity, see Maxwell E. Johnson, Praying and Believing in Early 

Christianity: The Interplay Between Christian Worship and Doctrine 

(Collegeville: Liturgical Press, 2013). 
11 Smyrnaeans 6. Translated from Ignatius of Antioch, Letters. In Cyril C. 

Richardson, ed & transl, Early Christian Fathers (New York: Touchstone, 

1996), 114. 
12 For the mystagogical catechesis of Cyril of Jerusalem, Ambrose, John 

Chrysostom and Theodore of Mopsuestia, see Edward Yarnold, The Awe-

Inspiring Rites of Initiation: The Origins of RCIA, (Collegeville: Liturgical 

Press, 1994), 65 -250. 
13 Pope Pius XII, Encyclical on the Liturgy: Mediator Dei, (November 20, 

1947), no. 48 (Henceforth referred to as MD). 
14See Aidan Kavanagh, ‘Response: Primary Theology and Liturgical Acts,’ 342. 

He argues that ‘with the presence of the verb, statuat, in the sentence, it is 

impossible to reverse the subject and predicate any more than one can reverse 

the member of the statement: the foundations support the house. Having said 

that, one cannot really say that the house supports the foundation. One must say 

something different.’  
15 Pope Francis, Apostolic Constitution Veritatis Gaudium: On Ecclesiastical 

Universities and Faculties, Art. 25 par. 1:1, January 29, 2018. 
16 Introduction to Ratio Fundamentalis Institutionis Sacerdotalis, March 19, 

1985. 
17 Paul Marshall, “Reconsidering ‘Liturgical theology’: Is there a Lex Orandi for 

All Christians?,” Studia Liturgical 25 (1995): 129-155.