Through the mediation of St. Faustina Kowalska (1905-38), Jesus has given us a teaching on God's mercy, and a new form of devotion known as the Divine Mercy. The devotion centers on veneration of the image of the merciful Jesus. The image was described by the Lord to Sister Faustina, a Polish nun, and then painted by her. The Divine Mercy devotion includes recitation of the Chaplet of Divine Mercy, celebration of the feast of Divine Mercy the first Sunday after Easter, and keeping holy the hour of Christ’s death.
On Sept. 13, 1935, in Vilnius (now the capital of Lithuania), Jesus "dictated" the words of the Chaplet of Divine Mercy to Sister Faustina. It is important to note that this took place after a vision of an angel, "the executor of Divine wrath," during which the mystic nun, terrified, began to "implore God for the world with words heard interiorly." This was recorded in her diary, Divine Mercy in My Soul (I, 196-197) [Stockbridge, Mass.: Marians of the Immaculate Conception, 2001; subsequent quotes are also from this source]. The next day Christ taught Sister Faustina to pray the chaplet, which she called "the prayer that serves to appease the wrath of God" (I, 197).