At first glance the Office can appear rather complex and, indeed, even discouraging. A recent comment prompted the thought of 'dissecting' an Hour to illustrate how things fit together. Comments as to whether this is useful or otherwise would be much appreciated.
Vespers is perhaps the most familiar Hour so seems a good place to start.
Today's feast is that of St. Joseph Calasanctius, Confessor. The rite is double. However, as tomorrow's feast, St. Augustine of Hippo, is also of the same rank Vespers are 'from the Chapter of the following' . In practice (with the 1911-13 reforms) this really is the same as saying first Vespers of St. Augustine with a commemoration of the previous feast of St. Joseph Calasanctius.
In the Sanctoral section of the Breviary (or Antiphonale etc) the respective Common is indicated - for St. Augustine this is the Common of Confessor-Bishops, this is found after the Sanctoral section towards the end of the Breviary.
Vespers has the following elements:
1) The prayer Aperi, Domine is said followed by Pater and Ave. These prayers are said in a low voice.
2) Deus in adjutorium... and its response Domine ad adjuvandum.... are sung followed by the Doxology.
3) The antiphons and psalms are taken from the occuring feria, Wednesday. (This is a characteristic of the 1911-13 reform - prior to this a double feast would take its antiphons and psalms from the Common - this meant that 'from the Chapter of the following' made more sense). The first antiphon Beati omnes, qui timent Dominum is sung in full and is then followed by Ps. 127. A slight complication: as the words of the antiphon are the same opening words of the psalm they are not repeated and so the psalm continues with the words: qui ambulant in viis ejus. At the end of the psalm the Doxology is sung followed by the antiphon Beati omnes, qui timent Dominum.
4) The pattern of antiphon, psalm, Doxlogy, antiphon is repeated for the other four psalms of the Hour: Confundantur omnes, qui oderunt Sion, Ps 128 Saepe expugnaverunt..., Gloria Patri..., Confundantur omnes, qui oderunt Sion. etc., until the last antiphon after the fifth psalm , Elegit Dominus Sion in habitationem sibi.
5) The chapter is taken from the Common: Ecce sacerdos magnus qui in diebus suis placuit Deo... The hymn from the Common follows: Iste Confessor Domini... followed by the versicle Amavit eum Dominus... and its response Stolam gloriae...
6) Then antiphon for the Magnificat, O Doctor optime...beate Augustine... is sung in full (conveniently printed in the Breviary under the texts for St. Augustine), followed by the Magnificat, Doxology and then the antiphon O Doctor... is repeated.
7) The greeting Dominus vobiscum is sung by the celebrant and after its response Oremus is sung followed by the prayer for the feast Adesto supplicationibus...
8) A commemoration of the 'before the chapter' office, St. Joseph Calasanctius, is now made. The antiphon for the Magnificat, Hic vir despiciens....is sung (but not the Magnificat again) and then the versicle Justum deduxit..., then Oremus and the collect Deus, qui per sanctum Josephum...
9) The above commemoration structure is repeated for St. Hermes whose feast is also August 28th: antiphon Iste sanctus..., versicle Gloria et honore..., response Et constituisti..., Oremus and the collect Deus, qui beatum Hermetum...
10) Now the normal ending of Vespers: Dominus vobiscum and its response, Benedicamus Domino and the response Deo gratias. Fidelium animae is said in a lower voice followed by Amen and a Pater said inaudibly.
11) The antiphon of the BVM follows: the versicle Dominus det nobis suam pacem with response Et vitam aeternam. Amen.; then Salve, Regina... its versicle Ora pro nobis... and response Ut digni... followed by Oremus and the collect Omnipotens sempiterne Deus..., the versicle Divinum auxilium... and response Amen.
12) At the end of the Office the prayer Sacrosanctae, the versicle Beata viscera... with response Et beata ubera.. followed by a final Pater and Ave.
The above took much longer to type than it would to actually sing or say! If this was helpful please remember in prayer the soul of the late Bernard Ford who first taught Rubricarius how to use the Breviary.