The Prayer of St. Gertrude is one of the most famous of the prayers for souls in purgatory. According to tradition, our Lord promised her that 1000 souls would be released from purgatory each time it is said devoutly:
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.
In the name of our Lord Jesus Christ I will begin this day.
I thank you, Lord, for having preserved me during the night. I will do my best to make all I do today pleasing to You and in accordance with Your will. My dear mother Mary, watch over me this day. My Guardian Angel, take care of me. St. Joseph and all you saints of God, pray for me.
O Jesus, through the Immaculate Heart of Mary, I offer You my prayers, works, joys and sufferings of this day for all the intentions of Your Sacred Heart, in union with the Holy Sacrifice of the Mass throughout the world, in reparation for my sins, for the intentions of all my relatives and friends, and in particular for the intentions of the Holy Father.
I wish to gain all the indulgences attached to the prayers I shall say and the good works I shall perform this day. Amen.