Be advised, this was found in a few minutes and takes both Catholic and Orthodox tradition…
“
Libera animas omnium fidelium defunctorum de poenis inferni et de profundo lacu”
Which translates to:
“
Free the souls of the faithful departed from the pains of the bottomless pit.”
These next few part’s I will quote verbatim from the source as I cannot personally fact check them (I looked this up as I was typing this so I can’t do any deep research or anything):
(1) “Here is something from the
Rule of Saint Maelruain, from the holy monastery of Tallaght. It is 8th century:
“There is nothing which a person does for a soul that has departed that does not help it, both vigil and abstinence, and singing the intercession and frequent blessings. Filii pro mortuis parentibus debent poenitere (google translate:
For the parents of the dead children should unrepentant).
A whole year therefore was
Saint Maidoc of Ferns (died 632), with all his people, living on water and biscuit so as to ransom the soul of Brandubh, son of Eochaidh, from hell.””
(2) This one is more of an anecdote: “As late as the 1530’s in the Latin Church, St Derfel in North Wales was believed to rescue souls from Hell. Thomas Cromwell acting on behalf of Henry VIII was put in charge of destroying images of the Saint, of which one wooden one was used as firewood to burn Blessed John Forrest.”
(3) last one: “The descent of Christ into Hades is one of the most mysterious, enigmatic
and inexplicable events in New Testament history. In today’s Christian
world, this event is understood differently. Liberal Western theology
rejects altogether any possibility for speaking of the descent of Christ
into Hades literally, arguing that the scriptural texts on this theme should
be understood metaphorically. The traditional Catholic doctrine insists that
after His death on the cross Christ descended to hell only to deliver the
Old Testament righteous from it. A similar understanding is quite widespread
among Orthodox Christians.
On the other hand, the New Testament speaks of the preaching of Christ in
hell as addressed to the unrepentant sinners: 'For Christ also died for sins
once for all, the righteous for the unrighteous, that he might bring us to
God, being put to death in the flesh but made alive in the spirit; in which
he went and preached to the spirit in prison, who formerly did not obey,
when God’s patience waited.
However, many Church Fathers and liturgical texts of the Orthodox Church
repeatedly underline that having descended to hell, Christ opened the way to
salvation for all people, not only the Old Testament righteous. The descent
of Christ into Hades is perceived as an event of cosmic significance
involving all people without exception. They also speak about the victory of
Christ over death, the full devastation of hell and that after the descent
of Christ into Hades there was nobody left there except for the devil and
demons.”
(this is where I got the information from, feel free to dive into the particulars:
Praying people out of hell - The Byzantine Forum)