Its use is obligatory in matters regarding the Roman Rite liturgy, but dioceses, countries and religious institutes may add duly approved appendices to it.
[3] The main source was the Martyrology of Usuard, completed by the Dialogues of Pope Gregory I and the works of some of the Fathers, and for the Greek saints by the catalogue known as the Menologion of Sirlet.
"The updated Martyrology contains 7,000 saints and blesseds currently venerated by the Church, and whose cult is officially recognized and proposed to the faithful as models worthy of imitation.
Then the actual text of the Martyrology entry is read, ending with the versicle taken from Psalm 116: Pretiosa in conspectu Domini – Mors Sanctorum eius ("Precious in the sight of the Lord – Is the death of his Saints").
A short Scripture reading may follow, which the reader concludes with Verbum Domini ("The word of the Lord"), to which those present respond: Deo gratias ("Thanks be to God").