Although the Ambrosian Divine Office shares many features with that of the Roman Rite, its structure is different in almost every respect. Vespers begins not with psalmody, but with a Lucernarium, a responsory originally sung while the lamps of the church were being lit. This is often (but not always) followed by an antiphon called “in choro”, because it was originally sung by the cantors standing around the throne of the celebrant. At Second Vespers of the Epiphany, this antiphon is repeated four times; traditionally, the first repetition was followed by three Kyrie eleisons, the second by Gloria Patri, the third by Sicut erat, and the fourth by three more Kyrie eleisons.
The following recording of the antiphon in choro for Epiphany was taken on Tuesday at the church of Santa Maria della Consolazione in Milan, during the solemn celebration of Second Vespers. (The video track freezes early on.) The printed music and text are given below. Many chants of the Ambrosian Office are sung multiple times by different persons or groups within the choir, a custom which was followed by the cantors at this ceremony.
Nicola de’ Grandi took an old photo of the choir of the Duomo of Milan during the chanting of this antiphon, and colorized it; the result is very nice.
