From the Golden Legend...
Like as Saint Gregory recounteth, in the fourth book of his Dialogues, that one of his monks named Justus when he came to his last end, he showed that he had hid three pieces of gold, and thereof sorrowed sore, and anon after he died. And then Saint Gregory commanded his brethren that they should bury his body in a dunghill, and the three pieces of gold with him, saying: Thy money be to thee in perdition. Nevertheless, Saint Gregory commanded one of his brethren to say for him every day mass, thirty days long, and so he did. And when he had accomplished his term, the monk that was dead appeared on the thirtieth day to one which demanded how it was with him, and he answered to him: I have been evil at ease unto this day, but now I am well. I have this day received communion, and the sacrifice of the altar profiteth not only to them that be dead, but also to them that be living in this world.
Prayer of St. Gertrude the Great...
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.