Indulgence Verses Promise

The Extraordinary Promise

Whoever approaches the Fountain of Life on this day will be granted complete forgiveness of sins and punishment. (Diary 300)

The soul that will go to Confession and receive Holy Communion shall obtain complete forgiveness of sins and punishment. On that day all the divine floodgates through which grace flow are opened. Let no soul fear to draw near to Me, even though its sins be as scarlet. My mercy is so great that no mind, be it of man or of angel, will be able to fathom it throughout all eternity. (Diary 699)

I want to grant complete pardon to the souls that will go to Confession and receive Holy Communion on the Feast of My mercy. (Diary 1109)

The Promise was made by the Lord to St. Faustina, as part of a private revelation to her. In reviewing her life as part of the canonization process, the Church determined that she lived a life of “heroic virtue" and ultimately the Holy Father, John Paul II, canonized her. The content of her private revelation, even though she is a saint, may still only command human credibility or faith. This means that an evaluation of the facts suggest to a reasonable person the truth of its content and its supernatural origin. Catholics reasonably accept it as coming from God, and believe it to be true, but are not obligated to accept it as a matter of divine faith. Reason itself suggests its truth, and so one could be acting unreasonably and imprudently by not accepting a private revelation, having given the facts and the Church's evaluation a fair hearing, but one could not be considered to be lacking supernatural Faith.

The Divine Mercy Indulgence

In the case of the Divine Mercy Indulgence, since it is act of the Successor of St. Peter to "bind and loose", it is a matter of divine revelation that IF we fulfill the conditions of the Indulgence (confession, communion, detachment from sin and prayers for the pope), that we will certainly receive what the Pope has promised in Christ's name: full remission of the temporal punishment due to our forgiven sins. This difference between private and public revelation explains why the Church institutionalized the Promise in the form of an Indulgence, and added Divine Mercy Sunday to the Church's general calendar. While both feasts and promise were inspired by a private revelation, they were made effective in the life of the Church by the authority of Christ's Vicar.

So, while the Promise seems easier to fulfill, lacking the difficult condition of detachment from even venial sin, we must still trust in God and throw ourselves on His mercy! This we should certainly try to do!  Yet, the Indulgence provides a certainty of Faith that the Promise does not, despite its own difficult condition of detachment from sin. If we try to satisfy both, we might succeed at one. What is most intrinsic to the Promise is the generosity of the Lord in forgiving us on this day, and so we may reasonably count on Him to provide the actual graces necessary to do what is required for the Promise, as we would have to do to obtain the Indulgence, as well.