Our Lady told us to pray for the souls in Purgatory every day!
November 6, 1986 “Dear children! Today I wish to call you to pray daily for souls in purgatory. For every soul prayer and grace is necessary to reach God and the love of God. By doing this, dear children, you obtain new intercessors who will help you in life to realize that all the earthly things are not important for you, that only Heaven is that for which it is necessary to strive. Therefore, dear children, pray without ceasing that you may be able to help yourselves and the others to whom your prayers will bring joy. Thank you for having responded to my call.”
Today bring to Me THE SOULS WHO ARE DETAINED IN PURGATORY, and immerse them in the abyss of My mercy. Let the torrents of My Blood cool down their scorching flames. All these souls are greatly loved by Me. They are making retribution to My justice. It is in your power to bring them relief. Draw all the indulgences from the treasury of My Church and offer them on their behalf. Oh, if you only knew the torments they suffer, you would continually offer for them the alms of the spirit and pay off their debt to My justice.
Most Merciful Jesus, You Yourself have said that You desire mercy; so I bring into the abode of Your Most Compassionate Heart the souls in Purgatory, souls who are very dear to You, and yet, who must make retribution to Your justice. May the streams of Blood and Water which gushed forth from Your Heart put out the flames of Purgatory, that there, too, the power of Your mercy may be celebrated.
Eternal Father, turn Your merciful gaze upon the souls suffering in Purgatory, who are enfolded in the Most Compassionate Heart of Jesus. I beg You, by the sorrowful Passion of Jesus Your Son, and by all the bitterness with which His most sacred Soul was flooded: Manifest Your mercy to the souls who are under Your just scrutiny. Look upon them in no other way but only through the Wounds of Jesus, Your dearly beloved Son; for we firmly believe that there is no limit to Your goodness and compassion. Amen.
Link to directions on how to pray the Divine Mercy Chaplet (by the Marians of the Immaculate Conception in Stockbridge, Massachusetts):
In Jesus, Mary and Joseph!
PS. This chapel at Surmanci contains a miraculous image of Jesus, Divine Mercy. You can read a short account of the miracles associated with the Image here:
PPS. Susan Tassone has written several books with prayers for the Souls in Purgatory. One of them is focused on St. Faustina and her dedication to the Souls in Purgatory. It is entitled: St. Faustina Prayer Book for the Holy Souls in Purgatory. It is available from Our Sunday Visitor: https://www.osv.com/Shop/Product?ProductCode=T1759