This heroic act in behalf of the souls in Purgatory consists in a voluntary offering made in their favor to the Divine Majesty, by any one of the faithful, of all works of satisfaction done by him in his life, as well as of all the suffrages which shall be offered for him after his death. By this offering he forgoes in their behalf only that special fruit which belongs to himself, so that he is not hindered thereby in praying for his own necessities, or those of others.
This act of charity, therefore, will not deprive us of any merit, for, by resigning our own claims on all works of satisfaction in favor of the souls departed, we shall gain for ourselves the special love of God, the Blessed Virgin Mary, and all the saints, according to the promise of Christ: "With what measure you mete, it shall be measured to you again." (Matth. vii. 2) Besides, the gratitude of the holy souls will induce them in turn to pray for us in Heaven, so that we may either escape Purgatory, or be blessed by a speedy deliverance therefrom.
This heroic act of charity was enriched with many indulgences by Pope Pius IX.
They are as follows:
I. The Indult of a Privileged Altar, personally every day of the year, to all priests who shall have made this offering.
II. A Plenary Indulgence, applicable only to the departed, to all the faithful who shall have made this offering whenever they go to Holy Communion, provided they visit a church or public oratory, and pray there for some time for the intention of His Holiness.
III. A Plenary Indulgence every Monday, to all who hear Mass in aid of the souls in Purgatory, provided they fulfill the other conditions mentioned above.
All indulgences granted or to be granted, which are to be gained by the faithful who have made this offering, may be applied to the holy souls in Purgatory.
Lastly, His Holiness, Pope Pius IX, having in view the young who have not yet made their First Communion, as well as the sick, those who are afflicted with chronic disease, the aged, farm laborers, prisoners and others who are debarred from Communion or unable to hear Mass on Mondays, declared that, for all the faithful who cannot hear Mass on Mondays, the Mass heard on Sundays should be available, and that in favor of those who have not yet made their First Communion, or who are hindered from receiving Communion, he has left it to the will of their respective Ordinaries to authorize confessors to commute the works here enjoined.
Prayer: We humbly beseech Thee. O Lord, graciously accept our indulgenced prayers for the suffering souls. We offer Thee, in their behalf, the Precious Blood of Jesus Christ, Thy Son, our Redeemer, and His infinite merits united with the merits of His most holy and immaculate Virgin Mother Mary, her ever-glorious spouse, St. Joseph, the holy Apostles, and all the Saints of Heaven, that by virtue of these merits our devotion may be to them a source of consolation and open to them the portals of Heaven, where they will love, praise, and glorify Thee, world without end. Amen.
Special Intercession: Pray for the souls, who, while on earth, made the heroic act of charity.
Lord grant them eternal rest and let perpetual light shine upon them. May they rest in peace. Amen. (Three times.)
Practice: Endeavor, every day, to perform an act of charity for the suffering souls.
Invocation: My Jesus, mercy!