"We will not have you ignorant, brethren, concerning them that are asleep, that you be not sorrowful, even as others who have no hope" (1 Thess. 4). The Church today has the same desire as the Apostle thus expressed to the first Christians. The truth concerning the dead not only proves admirably the union between God's justice and His goodness; it also inspires a charitable pity which the hardest heart cannot resist, and at the same time offers to the mourners the sweetest consolation. If faith teaches us the existence of a Purgatory where our loved ones may be detained by unexpiated sin, it is also of faith that we are able to assist them; and theology assures us that their more or less speedy deliverance lies in our power. Let us call to mind a few principles which throw light on this doctrine, every sin causes a twofold injury to the sinner: it stains his soul, and renders him liable to punishment. Venial sin, which displeases God, requires a temporal expiation. Mortal sin deforms the soul, and makes the guilty man an abomination to God: its punishment cannot be anything less than eternal banishment, unless the sinner, in this life, prevents the final and irrevocable sentence. But even then the remission of the guilt, though it revokes the sentence of damnation, does not cancel the whole debt. Although an extraordinary overflow of grace upon the prodigal may sometimes, as is always the case with regard to Baptism and Martyrdom, bury every remnant and vestige of sin in the abyss of Divine oblivion; yet is it the ordinary rule that for every fault satisfaction must be made to God's justice, either in this world or in the next.

On the other hand, every supernatural act of virtue brings a double profit to the just man: it merits for his soul a fresh degree of grace; and it makes satisfaction for past faults, in exact proportion to the value, in God's sight, of that labour, privation, or trial accepted, or that voluntary suffering endured, by one of the members of His beloved Son. Now, whereas merit is a personal acquisition and cannot be transferred to others, satisfaction may be vicarious; God is willing to accept it in payment of another's debt, whether the recipient of the boon be in this world or in the next, provided only that he be united by grace to the Mystical Body of Our Lord, which is one in charity. This is a consequence of the mystery of the Communion of Saints, as Suarez explains in his treatise on Suffrages.