St. Gregory the Great, in his Dialogues asks the question, “Is there anything at all that can possibly benefit souls after death?” teaches: “The Holy Sacrifice of Christ, our saving Victim, brings great benefits to souls even after death, provided their sins (are such as) can be pardoned in the life to come. For this reason the souls of the dead sometimes beg to have Liturgies offered for them … The safer course, naturally, is to do for ourselves during life what we hope others will do for us after death. It is better to make one’s exit a free man than to seek liberty after one is in chains. We should, therefore, despise this world with all our hearts as though its glory were already spent, and offer our sacrifice of tears to God each day as we immolate His sacred Flesh and Blood. This Sacrifice alone has the power of saving the soul from eternal death, for it presents to us mystically the death of the Only-begotten Son” (Dialogues IV: 57, 60, pp. 266, 272-3).
St. Gregory gives several examples of the dead appearing to the living and asking for or thanking them for the celebration of the Liturgy for their repose; once, also, a captive whom his wife believed dead and for whom she had the Liturgy celebrated on certain days, returned from captivity and told her how he had been released from his chains on some days—the very days when the Liturgy had been offered for him. (Dialogues IV: 57, 59, pp. 267, 270).
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