Hello,
Tried searching online but a couldn't find anything on the understanding of requiem/μνημόσυνο and its goal and roots etc like which ecumenical council established it...
Also I know that the ancient orthodox dogma does not have purgatory only heaven/hell and no one escape the judgment seat of Christ and where their soul ends up... so what does a requiem/μνημόσυνο aim to achieve?
Thanks as always
May we reach pascha / Kαλή ανάσταση vα φτάσουμε
Many weeks and many views but no wisdom?
If anyone has any views please reply, thanks 
Christ is risen!!! / Χριστός ἀνέστη!!!
Read the life of St. Xenia of St. Petersburg.
A few biographies say that St. Xenia witnessed the soul of her husband leaving hell for heaven after St. Xenia spent many years praying, fasting, and doing penances for her husband's soul, while most biographies omit any mention of this episode or the supposed vision that St. Xenia received. None of the biographies listed below mention this vision, which may have been a pious legend. Nevertheless, Xenia became a saint as she unselfishly gave away all her possessions and devoted her life to the service and salvation of others, including her beloved husband.
Her husband had supposedly died suddenly in a drunken brawl at a party, and with no time to confess, Xenia had feared for the salvation of his soul. She gave away her possessions, her clothing, and her home, and lived a life of poverty becoming known as a fool for Christ. Many miracles occurred during her life and at her tomb.
She was canonized in 1978 by the ROCOR. This was long before the ROCOR had joined the MP, but it was after the GOC had left the ROCOR in 1976.
Here are some biographies:
https://orthodoxwiki.org/Xenia_of_St._Petersburg
Lord Jesus Christ, have mercy on me a sinner.