Why did Akhmatova call her poem "The Requiem"?

Why did Akhmatova call her poem "Requiem"?
Requiem is the name of a Catholic mass offered for the soul of the deceased.
The poem is based on the personal drama of the author and the history of the entire nation during the years of repression.
Akhmatova talks about the arrest of her son, whom she visited in prison.
She and hundreds of other women stood in line for hours to learn the fate of their unjustly convicted loved ones.
Akhmatova compares the fate of women to that of the Virgin Mary, who witnessed the crucifixion of the Savior.

Akhmatova also compares the arrest of her son to the crucifixion of Christ, who accepted his death being an innocent man.

She conveys the sorrow the women felt in the hope of seeing their loved ones. Perhaps for the last time.
Akhmatova wanted no one to ever forget the main motif of the poem, the eternal sorrow that inhuman cruelty brings to the world.
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The clips have been created by the interregional public organization of large families "The Big Family" with the support of the Presidential Grants Fund. The information partner of the project is the Orthodox magazine "Foma" / foma.ru