St. Gertrude the Great's Prayer for the Souls in Purgatory

"Eternal Father, I offer Thee the Most Precious Blood of Thy Divine Son, Jesus, in union with the Masses said throughout the world today, for all the Holy Souls in Purgatory, for sinners everywhere, for sinners in the universal church, those in my own home and within my family. Amen."

According to the traditional story, Our Lord is supposed to have given this prayer to her with the promise that each time it is said, 1000 souls will be released from Purgatory. As Catholics we are not required to believe a private revelation. So, I will make no claims about how efficacious it is for releasing a specific number of souls. What is really important is that this is a very powerful prayer & God does work through it.