As this is the time of year when Ordos become available (and my own is now available from Lulu!) , I thought it might be timely to talk, over a few posts, about why you should use an Ordo; how to use an ordo effectively; and the key differences between the various ones available.
Ordos primarily serve two purposes I think: saving you a lot of time; and helping ensure you say the Office correctly.
Ordos as a time saver
First, even if you are reasonably expert when it comes to saying the Office, an Ordo can save you a lot of time.
In theory, for example, assuming you are reasonably familiar with the way the 'traditional' liturgical year works, with its several intersecting cycles, you could work out for yourself what season, month, week and day it is.
You could use the table in the front of your Diurnal or breviary that gives the dates of Easter and the other key 'moveable' feasts each year to work out what week of the liturgical year it is.
From August to November you could consult the notes in the temporale section of your Office book to work out what 'week' of the relevant calendar month it is.
And you can consult the sanctorale section to track what feasts fall on a particular date.
And you could use the 'two tables' (of occurrence and concurrence) to work out which particular Office to say when where are competing days and feasts.
Or you could just consult an Ordo!
Ordos for experts
If you are very familiar with the rubrics, you may not need a detailed Ordo.
In the case of my own Ordo, for example, you might just focus on a couple of key pieces of information in the topline entry, such as which Office is said on a particular day, and in some cases, whether Vespers is of the day of the week, or of the feast/special day.
For November 29 this year, for example, all you may need to know is:
Saturday
28 November – Class IV; Saturday of Our Lady
AT NONE: END OF TIME THROUGHOUT THE YEAR/ START OF ADVENT
1 Vespers of the First Sunday of Advent.
Compline: Marian antiphon Alma Redemptoris Mater henceforward.
That is, from Matins to None, the Office is for Saturday of Our Lady; from Vespers onwards the season is Advent, including a new Marian antiphon at Compline.
This assumes of course, that you know where to find the relevant pages in your book, and are sufficiently familiar with the rubrics for Vespers and Advent (or can work them out by reading the sometimes cryptic notes in your Office book).
Le Barroux
If you are in this category of a high degree of comfort with the rubrics, the Le Barroux Ordo supplies just this level of information, albeit in Latin. It is worth noting though, that Le Barroux not strictly follow the 1962 rubrics in all cases (including I Vespers for Class II feasts for example), and includes feasts particular to the monastery and its location.
The Le Barroux Ordo is also worth considering acquiring, though, if you follow their podcasts of the Office, so you know what you are going to be listening to (and purchasing a copy and perhaps making a donation if you are in a position to do so is a nice thank you for their efforts in making the livestream available).
Divinum Officium
Another option for a 'bare bones' Ordo is the monastic option on the Divinum Officium website, which is now keyed to the 1962 Benedictine calendar.
Monastic calendars
The other source worth noting is calendars put out by individual monasteries. These typically include the dates of feasts and so forth celebrated the monastery, which can be an important source of information on feasts particular to that monastery or congregation if you are one of their Oblates.
Hunting down chants and texts in other books
A second way an Ordo can save you some time is in linking you up to sources for the chants (which are typically in pre-1962 books, and so may be scattered in different places, or across different books). My own Ordo provides page numbers to the Antiphonale Monasticum and other chant books for this purpose.
In addition, particular monasteries/countries/regions celebrate feasts particular to them, and so aids to finding the texts for these - such as to the 'in some places' supplement in the Diurnal and the Clear Creek supplement to the Antiphonale - can be helpful. As monasteries and others take advantage of the provisions allowing the celebration of new saints (and others now permitted), this is likely to become a growth area in future!
Ordos to help you get it right
Even the most minimalist Ordos can be a key aid to ensuring you say the Office correctly using an Office book: knowing what week of the liturgical year it is, what Office is celebrated on it is an important start,
If you are less familiar with the Office though, having a bit more information than this can help.
For that reason, my own Ordo provides page numbers for texts in the Monastic Diurnal, and chants in the Antiphonale, where the Office of the day differs from the 'ferial' or ordinary day Office.
So for the entry I noted above, for the First Sunday of Advent, you get:
Sunday 29 November – First Sunday of
Advent, Class I
Matins: Invitatory antiphon (Regem venturum Dominum), hymn (Verbum
supernum), antiphons, versicles and canticles of Advent; readings, responsories
and collect of Sunday I of Advent.
Lauds: Antiphons, chapter, responsory, hymn, versicle, Benedictus antiphon and collect of the First Sunday of Advent, MD 4*/AM 187 ff.
Prime: Antiphon 1 of Lauds, MD 6-7*/AM 187.
Terce to None: Antiphon, chapter, versicle and collect of Sunday Advent I, MD 7-8*/AM 189-90 ff.
2 Vespers: Antiphons, chapter, responsory, hymn and collect as for 1 Vespers,
MD 1*/AM 186 ff; versicle and Magnificat
antiphon of 2 Vespers, MD 8-9*/AM 190.