The feast of SS Simon and Jude is a double feast of the second class. The feast of these two apostles is kept on the anniversary of the transfer of their relics to Old St. Peter's in Rome in the seventh century. St. Simon is traditionally believed to have been martyred by a curved sword and St. Jude, also known as Thaddaeus, was martryed by a club. The two probably met, preaching the Gospel, in Mesopotamia.
At Mattins the antiphons and psalms are taken from the Common of Apostles. The lessons in the first nocturn are from St. Jude's Epistle. In the second nocturn the fourth lesson is an historical one and the fifth and sixth from a sermon of St. Gregory. In the third nocturn the homily on St. John's Gospel is from the writings of St. Augustine.
At Lauds the Dominical psalms are sung under the antiphons from the Common. Prime is festal with psalm 53 and the lectio brevis Ibant Apostoli. Festal psalmody is used at the Little Hours.
Mass is sung after Terce. The Gloria and Creed are sung and the preface is that of the Apostles. Following the rubrics in the Gradual, and custom, four cantors should lead the choir. Liturgically erudite men such as the late Fr. Clement Russell and Fr. Quentin Montgommery-Wright would have their cantors in red copes on such a day. Vespers and Compline conclude the feast.
In the 'liturgical books of 1962' the feast is second class and one of the few days to retains three nocturns. At the Little Hours the ferial antiphons and psalter are used.