St. Faustina writes in her diary that on February 22, 1931, Jesus appeared to her as "King of Divine Mercy". In this apparition Jesus revealed to her, her purpose: "To spread the devotion of the Divine Mercy of God." And to spread his message of the Divine Mercy.

Which is the message?
"The message of Mercy is that God loves us, loves us all, regardless of the magnitude of our sins"
· God wants us to come to Him praying, repenting of our sins and asking for mercy
· God wants us to receive mercy and let it flow to others, giving them love and forgiveness, as He gives
· God will give us his mercy in the same amount as we trust in Jesus

What is the prayer for mercy?
O God of great mercy! Infinite Goodness, today all mankind cries out from the depths of its misery, to your mercy, to your compassion, O God; and crying with the loud voice of its misery. Forgiving God, do not reject the prayer of the outcasts of this Earth. O Lord, inconceivable goodness that perfectly knows our misery and knows that with our own strength, we cannot ascend to You. I implore you, hasten your grace and incessantly multiply your mercy in us to faithfully fulfill your holy will throughout our lives and the time of our death. The omnipotence of Your mercy protect us from the arrows of the enemies of our salvation, so that with confidence, as Your children, we await Your last coming, that day known to you alone. And despite all our misery, we expect to receive all that Jesus has promised us, because Jesus is our hope; through His merciful heart, as through an open door, we enter heaven. (Diary, 1570)

Jesus said:
"Through my Mercy you will obtain everything, if what you ask is according to my will (...)
Pray unceasingly this chaplet that I have taught you. Whoever will recite it will receive great mercy at the hour of death; the priests will recommend it to sinners as their last hope of salvation.
Even the most hardened sinner, if he prays this Chaplet only once, he would receive grace from My infinite mercy. I wish the whole world to know My mercy; I desire to grant unimaginable graces to souls who trust in My mercy "(Diary # 731 and # 687).

"I will defend as My own glory every soul, that prays this Chaplet, at the time of death, or when others pray together with the dying, he will receive the same forgiveness. When (this chaplet) is prayed near a dying, God's anger is placated and unfathomable mercy envelops the soul and the depths of My tender mercy are moved by the Passion of My Son "(Diary 811).

In her diary Faustina wrote: "During Holy Mass, I saw the Lord Jesus nailed to the cross, in great sufferings. A silent groan came out of his heart, a moment later He said:

"I wish, I wish the salvation of souls; help me, my daughter, to save souls. Join your sufferings to My Passion and offer them to the Heavenly Father for sinners." (Diary 1032)