Jesus promised St. Faustina that those who received Holy Communion in a state of grace on Divine Mercy Sunday (Feast of Mercy) would receive “the complete remission of sins and punishment”(Diary 699).
The theologian who examined St. Faustina’s writings for the Holy See, Rev. Rozycki, explained that, “this is the promise of a complete renewal of baptismal grace, and in a sense it is like a second Baptism.”
Fr Rozycki wrote: “Christ made the remission of all sins and punishment contingent on the reception of Holy Communion on the Feast of Divine Mercy. It is most obvious that in order to affect a complete forgiveness of sin and punishment the Holy Communion received on the Feast of Mercy must be received worthily, and must also fulfill the basic requirements of the Divine Mercy devotion. However, received unworthily, without trust in Divine Mercy and devoid of some deed of mercy toward neighbor, it would be a contradiction of devotion to the Divine Mercy. Instead of the exceptional grace, it would bring down upon the recipient the Divine Wrath (Stackpole, 2004, p. 113-114).”
Our Lord Speaks:
“Ask of my faithful servant (Father Sopocko) that, on this day, he tell the whole world of My great mercy; that whoever approaches the Fount of Life (Holy Communion) on this day will be granted complete remission of sins and punishment…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 (Diary 299, 300, 251)
What Father Rozycki goes on to say about the grace promised by Jesus is mind boggling.
“The most exceptional grace promised by Jesus for the Feast of the Divine Mercy is greater than a plenary Indulgence, which only consists of a remission before God of temporal punishment due to sins already forgiven, and never the remission of sins itself (Stackpole, 2004, 113-114).” (Refer to Catechism 1471 on Plenary Indulgences)
Theologically, there is no possibility of a second baptism. Baptism can only be received once and through baptism all is washed clean- “complete remission of sins and punishment.” Through baptism we become adopted sons and daughters of the Most High- (Priest, Profit and King). What is meant in the quote above is that its power is like a second baptism. If God is able to bestow this grace through the sacrament of Baptism, why would He not be able to bestow it- if He so wishes-through the Eucharist, which is the greatest sacrament. It is clearly obvious that in order to receive these graces of Divine Mercy Sunday, one must be in the state of grace and partake of Our Lord worthily.