There are five Saturdays throughout the year when the church gathers as community to remember all the dead (on Meatfare Saturday [two Saturdays before the beginning of Great Lent], the second, third, and fourth Saturdays of Great Lent, and the Saturday before pentecost). These are known as the Soul Saturdays (Zaduzda Subbbotu).
In addition, in the Slavic tradition, the Saturday closest to the feast of St. Demetrius Day (Ocober 26) is also a day of remembering the dead. It was originally instituted to commemorate the soldiers who fell in the Battle of Kulikovo (fought beteen Russia and the Mongol-Tatar Golden Horde in 1380), under the leadersthip of St. Demetrius of the Don.
Today in America, most Orthodox view Soul Saturdays as days when they provide a list of their deceased relatives and friends to the priest and a requiem Divine Liturgy is celebrated followed by a Parastas, or, a Panikhida is celebrated in the evening, just prior to the Saturday evening vigil.
In actuality, the whole day is dedicated to the deceased with the variable parts of the daily office (Vespers, Compline, and Matins) commemorating the dead.
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O faithful, let us commemorate today, all those who have fallen asleep from times beyond memory, and all those who have lived in true faith, each one individually. Let us praise the Lord and Savior, praying to Him with fervor, that at the time of judgment they may give a good account to our God who is to judge the earth, so that they may stand joyfully at His right hand in the company of the just, as brilliant heirs of the saints, and that they may deserve His heavenly kingdom. (Vespers, Stichera at Psalm 140)
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Alleluia! Alleluia! Alleluia!
Blessed are they whom You have chosen and received, O Lord.
Alleluia! Alleluia! Alleluia!
They are remembered from generation to generation.
Alleluia! Alleluia! Alleluia! (Vespers, Prokeimenon and at Matins replacing God is the Lord.)
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Remember, O Lord and Savior, our parents and grandparents, all of our ancestors and elders, who from the beginning until these last days, have died in righteousness and true faith.
When Your angel shall sound the trumpet on the last day, O Lord, to call all flesh to the resurrection, then O Christ, give rest to all Your servants.
To all the faithful whom You have taken to Yourself from every age of life, the old and the young, youths and those in the prime of life, children and newborn babies, grant, O Lord, Your eternal rest.. (Matins, from the Canon)
Authored by Ben Kalemba