[Bug]: Pentecost Vigil Mass (extended readings) not handled in readings source data

[matthewa26]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

In the source data for the Pentecost liturgies, there is only an option for "vigil" and "day". However, on the USCCB website (this is focused on the en.json file but likely extends to other languages as well), there is an option for extended readings for the Pentecost Vigil.

The current JSON shows the following (with line numbers):

468     "Pentecost": {
469         "vigil": {
470             "first_reading": "",
471             "responsorial_psalm": "",
472             "second_reading": "",
473             "gospel_acclamation": "",
474             "gospel": ""
475         },
476         "day": {
477             "first_reading": "",
478             "responsorial_psalm": "",
479             "second_reading": "",
480             "gospel_acclamation": "",
481             "gospel": ""
482         }
483     },

Expected Behavior

I'm not sure what the implementation would look like, but there should be an option to choose the normal readings or the extended readings. One option would be to do something like this (similar to the Easter Vigil):

468     "Pentecost": {
469         "vigil": {
470             "first_reading": "",
471             "responsorial_psalm": "",
472             "second_reading": "",
473             "gospel_acclamation": "",
474             "gospel": ""
475         },
476         "vigilSupplement": {
477             "first_reading": "",
478             "responsorial_psalm_1": "",
479             "second_reading": "", 
480             "responsorial_psalm_2": "",
481             "third_reading": "",
482             "responsorial_psalm_3": "",
483             "fourth_reading": "",
484             "responsorial_psalm_4": "",
485             "epistle": "",
486             "gospel_acclamation": "",
487             "gospel": ""
488         },
489         "day": {
490             "first_reading": "",
491             "responsorial_psalm": "",
492             "second_reading": "",
493             "gospel_acclamation": "",
494             "gospel": ""
495         }
496     },

I thought about the idea of just making everything past the second reading optional, but since the Responsorial Psalm is different between the different liturgies, it would likely need to be split out. The extended readings are listed as a supplement on the USCCB website.

Steps To Reproduce

1. Look at the USCCB's website: https://bible.usccb.org/bible/readings/052426-Extended
2. Look at the source data for Pentecost in the API's Sundays in Year A JSON (English): Lines 468-483

Environment

N/A

Anything else?

Version

dev (Unstable)

[JohnRDOrazio]

In Italy the "extended readings" are for a prayer vigil. It is customary to celebrate a prayer vigil for Pentecost in Italy, and until recently each parish would prepare their own prayer vigil. Recently however, it was decided that this prayer vigil should have a more liturgical tone, and be established in a universal manner to avoid too much "pastoral creativity". For example, here is the schema prepared by the Italian Bishops Conference for the 2025 Prayer Vigil: https://www.chiesacattolica.it/wp-content/uploads/sites/31/2025/05/29/veglia_pentecoste2025_doc_acc-1.pdf . In the United States, does the schema "Extended Vigil" apply to the actual Vigil Mass, or are they used for a prayer vigil?

[matthewa26]

There is a supplement to the liturgy available for the vigil Mass. Let me see if I can find a document from the USCCB on the matter.

[matthewa26]

Here's a news article that talks about the extended vigil: https://www.ncregister.com/features/little-known-pentecost-vigil-mass-is-a-hidden-gem-of-the-catholic-liturgy

Here's a USCCB newsletter talking about the lectionary 62 supplement, which is the Pentecost extended Vigil: https://www.usccb.org/resources/newsletter-2016-09.pdf

Here's the 2026 liturgical calendar from the USCCB, which details the extended vigil (pg 27): https://www.usccb.org/resources/2026cal.pdf

[JohnRDOrazio]

It is for cases like these, that it would be useful to build up a team of expert liturgists around the Liturgical Calendar API project, so that we can better coordinate across various countries with the correct intent of each Bishops Conference, finding the best technological solution to represent such intent. In any case the resources you provided are quite helpful.

If we were to consider the case of the United States, we could consider adding an "extendedVigil" object alongside "vigil" and "day".

If we were to consider the case of Italy, we could consider adding a "prayerVigil" object alongside "vigil" and "day".

Perhaps the best approach is to align as closely as possible with the Latin edition. I see in the second link you provided a mention:

For the extended form of the Pentecost Vigil Mass (first suggested in 1988 and formally added to the Missale Romanum in 2008)

I'm seeing that I don't have a PDF of the 2008 Latin edition on hand, that would be useful to have. With the Catholic Digital Commons Foundation established, one of the next steps will be to build up a project team and project plan. Part of this plan could be to purchase a copy of all Roman Missals and Lectionaries, as reference material.

[matthewa26]

That sounds like a fantastic idea! We could either have a traveling set or a project team member who hosts all of them, and can quickly provide references and validate information.