Prayer for Souls in Purgatory

A reader who read my article on Purgatory earlier this week sent me the following prayer given by the Lord to St. Gertrude.

"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."

Our Lord told her it would release many souls from Purgatory each time it was said.