Aquinas, Augustin, Benedict and Corbon on Seven and Eight in the Psalms and the Liturgy.

The Pattern of the Liturgy is a Model for Design in Beauty that Will Draw People To Your Work

In his book the Wellspring of Worship, Jean Corbon talks about the significance of the numbers seven and eight in the liturgy. In the Old Testament, seven is the number that signifies God’s covenant and so time is ordered according to it with seven days in a week. The book of Genesis describes the institution of this, of course, in the Creation story; and the symbolism is reinforced with the appearance of the seven-colour rainbow in the sky when Noah is saved and the covenant with all the earth is reinstituted. Eight is the number of new covenant ushered in with the incarnation, life,death and resurrection of Christ. So the eighth day is Sunday, which is simultaneously the first day of the next week and the last, the eighth of the previous one. The transition of the old to the new is symbolized by the operation of adding one to seven. 

In thinking about this, it causes me to think of the progression through sacred time not as a linear passage, but rather a helical one. As each day moves forward in time, we can imagine a vector shift that is forward and upward and turns an angle, so that by the time eight days have progressed, a full circle has been turned and the eighth is directly above the first. We have traced out seven days of the week, and then the significant addition of another day takes us to another Sunday, sitting vertically above the previous Sunday which is a pitch of the thread beneath it. So although it has the same name it is a new day and marks simultaneously the end of the last octave and the beginning of the next. This way by following the liturgical weekly cycle  we trace a holy spiral,upwards to heaven. All we have to do is participate in the liturgical life and we are transported along this path. 

Corbon describes how in the context of the year Easter is at the centre of the year. To emphasize its importance there are eight consecutive eighth days in the Octave of Easter (and Christmas). It is in effect a week of Sundays. Prior to Easter there are seven weeks of Lent (although it is actually a couple of days short of a complete seven) and afterwards there are the 50 days of Pentecost. He describes how the 50 days are seven weeks of seven days, 49 days in all, that are brought to completion by the addition of an eighth eighth day at the end. 

This pattern of seven being resolved finally in eight is present within the structure of each day also. Quoting Psalm 118 in Chapter 16 of his Rule, St Benedict establishes the eight traditional Offices (seven daytime and one night time) and their hours in the Divine Office: ‘ “Seven times in the day,” says the Prophet, “I have rendered praise to You” (Ps. 118[119]:164). Now that the sacred number of seven will be fulfilled by us if we perform the Offices of our service at the time of the Morning Office, of Prime, of Terce, of Sext, of None,of Vespers and of Compline,since it was of these day Hours that he said,”Seven times in the day I have rendered praise to You” (Ps. 118[119]:164). For as to the Night Office the same Prophet says,”In the middle of the night I arose to glorify You” (Ps. 118[119]:62). Let us therefore bring our tribute of praise to our Creator ” for the judgments of His justice” at these times:the Morning Office, Prime, Terce,Sext, None,Vespers and Compline; and in the night let us arise to glorify Him.’ 

This means that the prayer of the Church, which is the prayer of Christ himself, ushers the world forward on a path of redemption through sacred time that is a triple helix. The tight daily helix spirals its way on the weekly helix, which in turn sits on a giant helix which rotates once in a year. 

Speaking in a sermon for Low Sunday, which is reproduced in the Office of Readings for that day, eight days after Easter, Augustine refers to how the Octave was anticipated in Old Testament: ‘This is the octave day of your new birth. Today is fulfilled in you the sign of faith that was prefigured in the Old Testament by the circumcision of the flesh on the eighth day after birth. When the Lord rose from the dead, he put off the mortality of the flesh; his risen body was still the same body, but it was no longer subject to death. By his resurrection he consecrated Sunday, or the Lord’s day. Though the third after his passion, this day is the eighth after the Sabbath, and thus also the first day of the week.’ 

The psalms as we can see from the quotes of Benedict above, though placed in the Old Testament, anticipate the New also. This should be no surprise. For as St Thomas Aquinas tells us in his commentary on the psalms, this is a special book that contains all the content of theology: ‘The material is universal for while the particular books of the Canon of Scripture contain special materials, this book has the general material of Theology as a whole.’ Then in referring to their special place in the liturgy where they are to be sung he says: ‘This is what Dionysius [the Areopagite] says in Book 3 of the Celestial Hierarchy,the sacred scripture of the Divine Songs (Psalms) is intended to sing of all sacred and divine workings.’ 

This points to the psalms as a special source of wisdom, especially in the context of the liturgy. Given that the purpose of education is to instill wisdom, one wonders why more educational institutions do not have the liturgy of the hours, as well as Mass offered daily (as traditional universities used to). (I wrote about this value of psalms and the liturgy in education as a source of wisdom, here.) 

St Thomas goes on to explain in the same commentary that not only is the content containing all of theology but also the very structure of the book itself conforms to the symbolism of seven and eight: ‘The first distinction is that there are one hundred and fifty psalms; this is a mystery, because this number is composed of 70 and 80. By 7, from which 70 is named, the course of this time is signified, which is carried out in seven days; by 8, from which 80 is named, the state of the future life.   For the number eight according to the Gloss concerns those who rise from the dead; and it signifies that in this book there is a treatment of those things that pertain to the course of the present life, and to future glory. Again, by seven the old testament is signified. The fathers of the old testament observed that which is seventh: they observed the seventh day, the seventh week, the seventh month, and the seventh year of the seventh decade, which is called the Jubilee. By eight the new testament is signified: we celebrate the eighth day, namely the Lord’s Day, on account of the solemnity of the Lord’s resurrection; and in this book are contained the mysteries of the old and new testament.’ (The Gloss is the glossa ordinaria, a standard biblical commentary based upon comments of the Fathers, predominantly Jerome, Augustine, Bede and Gregory.)

I would add that this 7:8 structure seems to echo the lenten/pentecostal relationship that Corbon describes as well as the Old/New Testament convenantal relationship.

The proportion of this structure is appropriate to the book of psalms, relating as it does to the old and new covenant, and this lends a greater beauty to the book as a whole. We respond to this intuitively as we read it, and so the structure of it aids our understanding. Just as God offers wisdom through this book in a pattern appropriate to it, so we are made by Him so that this is how we naturally desire to take it in, and we respond to the beauty of it. When this is presented in its appropriate context, in the liturgy, which itself conforms to these patterns, the power is multiplied. 

If we talk of octaves in casual conversation, most people will assume we are talking about music and of course we find that the beautiful patterns of harmony in music correspond to this also. The musical scale is seven notes, and the eighth is higher still, simultaneously the last note of the previous octave and the first of the next. What is extraordinary is that the peculiarly human apprehension of this progression hears this eighth note as one that is at a higher pitch, yet of the same quality – for example a high and low C. One might think of this, perhaps, as a musical representation of Easter Sunday and Low Sunday!

How does this relate to design? Because number can be used to order man’s activity in time and space, potentially all human activity can be made to conform to this liturgical beauty. The symbolism of eight and seven is only one pair of examples that could govern it. So we could use eight sided geometric shapes to indicate this. Within music, harmonious relationships can be described numerically a different way by consideration of the relative lengths of pieces of string (or lengths of pitch pipe) that produce particular notes when plucked (or blown). To describe the interval of an octave you would have one string twice the length of another, so this means that the ratio 1:2 is another way of showing the harmony of an octave. You could have a picture, for example bounded by a rectangle, with one side twice the length of another. As many will know, the other fundamental music harmonies contained within the octave, the fourth and the fifth produce ratios of 3:4 and 2:3. So a simple design for a church with ratio 1:2:3 for the main structure of it, invokes the whole liturgical logic that lies behind it. There are many more proportions in the tradition beside these, but all point to and are derived from this liturgical principle. 

Man is made for liturgy, and it is liturgical man that is responding when we hear the beauty or the harmony in music or in the natural world, for these relationships echo the patterns of the liturgy and of heaven. The music to which the psalms are applied itself follows these patterns too through the intervals that it describes in the various modes.

As we know St Augustine said that he who chants his prayers prays twice. In reality, I would say, it is even more than that: a common pattern of beauty runs through the structure of the liturgy (daily, weekly, seasonal and annual), the text of the psalms and the music to which they are applied, and ideally even the church building in which we sing them.

What might seem at first the ordinary act of chanting a psalm to its simple tone while marking the Hour, is in fact invoking a whole host of intertwining harmonious relationships. We hear only one note at a time; yet it speak to us of something that is dazzling in its beauty and complexity. The wonder of all of this is that God made us all so that we can grasp this effortlessly: each hears monophony and apprehends symphony.

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David is an Englishman living in New Hampshire, USA. He is an artist, teacher, published writer and broadcaster who holds a permanent post as Artist-in-Residence and Lecturer in Liberal Arts at the Thomas More College of Liberal Arts. The Way of Beauty program, which is offered at TMC, focuses on the link between Catholic culture, with a special emphasis on art, and the liturgy. David was received into the Church in London in 1993. Visit the Way of Beauty blog at

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