Sister Maria Faustina Kowalska was a young religious in a convent in Krakow, Poland. She died on October 5, 1938. However, during the period between 1931 and 1938, our Lord appeared to her several times with messages about His great mercy. In obedience to our Lord and to her spiritual director, she put all of this into writing.
After a thorough examination of the matter, on April 15, 1978, the Holy See permitted the devotion to the Divine Mercy according to the writings of Sister Faustina. On April 18, 1993, Sister Faustina was beatified. In the year 2000, Sister Faustina was canonised.
Saint Faustina described our Lord’s appearance to her in 1931: “In the evening, when I was in my cell, I became aware of the Lord Jesus clothed in a white garment. One hand was raised in blessing, the other was touching the garment at the breast. From the opening of the garment at the breast there came forth two large rays, one red and the other pale. In silence I gazed intently at the Lord; my soul was overwhelmed with fear, but also with great joy. After a while Jesus said to me, ‘paint an image according to the pattern you see, with the inscription: Jesus, I trust in You.’”
Our Lord explained this image to her: “The pale ray stands for the Water [of sanctifying grace] which makes souls righteous; the red ray stands for the Blood which is the life of souls. These two rays issued forth from the depths of My most tender Mercy at that time when My agonizing Heart was opened by a lance on the Cross. … Fortunate is the one who will dwell in their shelter, for the just hand of God shall not lay hold of him.”
Jesus also spoke of a Feast of the Divine Mercy and Confession and Holy Communion on that day. He said: “My daughter, tell the whole world about My inconceivable mercy. I desire that the Feast of Mercy be a refuge and a shelter for all souls, and especially for poor sinners. On that day the very depths of My tender mercy are open. I pour out a whole ocean of graces upon those souls who approach the fount of My mercy. The soul that will go to Confession and receive Holy Communion shall obtain complete forgiveness of sins and punishment. On that day are opened all the divine floodgates through which graces flow. 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. Everything that exists has come from the very depths of My most tender mercy. Every soul in its relation to Me will contemplate My love and mercy throughout eternity. The Feast of Mercy emerged from My very depths of tenderness. It is My desire that it be solemnly celebrated on the first Sunday after Easter. Mankind will not have peace until it turns to the Fount of My mercy.” Pope John Paul II established the Second Sunday of Easter as Divine Mercy Sunday in the year 2000.
Adapted from catholicculture.org