The message and devotion to Jesus as The Divine Mercy is based on the writings of Saint Faustina Kowalska, a  
  Polish nun who, in obedience to her spiritual director, wrote a diary of about 600 pages recording the revelations   
  she received about God’s mercy. Even before her death in 1938, the devotion to The Divine Mercy had begun to 

  The message of mercy is that God loves us — all of us — no matter how great our sins. He wants us to recognize  
  that His mercy is greater than our sins, so that we will call upon Him with trust, receive His mercy, and let it flow  
  through us to others. Thus, all will come to share His joy. It is a message we can call to mind simply by  
  remembering ABC.

  A — Ask for His Mercy. God wants us to approach Him in prayer constantly, repenting of our sins and asking Him  
          to pour His mercy out upon us and upon the whole world.
  B — Be merciful. God wants us to receive His mercy and let it flow through us to others. He wants us to extend 
          love and forgiveness to others just as He does to us.
  C — Completely trust in Jesus. God wants us to know that the graces of His mercy are dependent upon our trust. 
          The more we trust in Jesus, the more we will receive.

  The Divine Mercy Devotion
  Devotion to The Divine Mercy involves a total commitment to God as Mercy. It is a decision to trust completely in 
  Him, to accept His mercy with thanksgiving, and to be merciful as He is merciful.

  The devotional practices proposed in the diary of St. Faustina are completely in accordance with the teachings of  
  the Church and are firmly rooted in the Gospel message of our Merciful Savior. Properly understood 
  and implemented, they will help us grow as genuine followers of Christ.

  The Lord Jesus chose Sr. Mary Faustina as the Apostle and "Secretary" of His Mercy, so that she could tell the 
  world about His great message. In the Old Covenant — He said to her —I sent prophets wielding thunderbolts to 
  My people. Today I am sending you with My mercy to the people of the whole world. I do not want to punish 
  aching mankind, but I desire to heal it, pressing it to My Merciful Heart (Diary 1588).

  The mission of Sister Mary Faustina consists of 3 tasks:

  – reminding the world of the truth of our faith revealed in the Holy Scripture about the merciful love of God toward 
     every human being.

  – Entreating God's mercy for the whole world and particularly for sinners, among others through the practice of 
     new forms of devotion to the Divine Mercy presented by the Lord Jesus, such as: the veneration of the image of 
     the Divine Mercy with the inscription: Jesus, I Trust in You, the feast of the Divine Mercy celebrated on the first 
     Sunday after Easter, chaplet to the Divine Mercy and prayer at the Hour of Mercy (3 p.m.). The Lord Jesus 
     attached great promises to the above forms of devotion, provided one entrusted one's life to God and practiced 
     active love of one's neighbor.

  – The third task in Sr. Mary Faustina's mission consists in initiating the apostolic movement of the Divine Mercy  
     which undertakes the task of proclaiming and entreating God's mercy for the world and strives for Christian 
     perfection, following the precepts laid down by the Blessed Sr. Mary Faustina. The precepts in question require 
     the faithful to display an attitude of child-like trust in God which expresses itself in fulfilling His will, as well as in 
     the attitude of mercy toward one's neighbors. Today, this movement within the Church involves millions of 
     people throughout the world; it comprises religious congregations, lay institutes, religious, brotherhoods, 
     associations, various communities of apostles of the Divine Mercy, as well as individual people who take up the 
     tasks which the Lord Jesus communicated to them through Sr. Mary Faustina.

The mission of the St. Faustina was recorded in her Diary which she kept at the specific request of the Lord  
Jesus and her confessors. In it, she recorded faithfully all of the Lord Jesus' wishes and also described the encounters between her soul and Him. Secretary of My most profound mystery — the Lord Jesus said toSt. Faustina — know that your task is to write down everything that I make known to you about My mercy, for the benefit of those who by reading these things will be comforted in their souls and will have the courage to approach Me (Diary 1693). In an extraordinary way, St. Faustina's work sheds light on the mystery of the Divine Mercy. It delights not only the simple and uneducated people, but also scholars who look upon it as an additional source of theo-logical research. The Diary has been translated into many languages, among others, English, German, Italian, Spanish, French, Portuguese, Arabic, Russian, Hungarian, Czech and Slovak.

The history and mission of this devotion according to St. Faustina