There are two kinds of synaxaria - simple synaxaria, which are merely lists of the saints arranged in the order of their anniversaries, e.g.
The list of anniversaries of a church formed its Martyrology.
In the early days each church confined itself to celebrating its own martyrs; but it was not long before it became customary to celebrate the anniversaries of martyrs of other churches.
Apparently they were at first arranged in a series of anniversaries separate from that of the martyrs, as seems to be shown by the existence at Rome of the Depositio episcoporum side by side with the Depositio martyrum; the two lists seem to have been combined, as in the calendar of Carthage, which includes the dies nataliciorum martyrum et depositiones episcoporum.
REQUIEM, the name of a solemn mass for the dead (Missa pro defunctis) in the Roman Church, appointed 'to be sung on All Souls' Day, in memory of all "faithful departed," at funeral services, and at the anniversaries of the death of particular persons.
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