On this day the Catholic Church remembers St. Faustina Kowalska, 1905-1938.
"Sister Mary Faustina, an apostle of the Divine Mercy, belongs today to the group of the most popular and well-known saints of the Church. Through her the Lord Jesus communicates to the world the great message of God's mercy and reveals the pattern of Christian perfection based on trust in God and on the attitude of mercy toward one's neighbors."
--from the Biography  at the Vatican web site.
But not all Catholics find St. Faustina or her private revelations helpful or credible.
"From 1931 to her death in 1938, Faustina reported a staggering range of spiritual experiences, including visions, a hidden stigmata, bilocation, the reading of human souls, prophecy, as well as mystical engagement and marriage. She also believed that Jesus, Mary and several saints, such as Teresa, delivered private revelations to her on a regular basis, which she recorded in a diary that eventually stretched over more than 600 pages. (It was later published with the title, Divine Mercy in My Soul.)"
--"Beatification Q&A #4: What’s the Divine Mercy connection?"  by John Allen, NCR Today, April 28, 2011.
"Jesus spoke to her about all manner of things (once reassuring her that she would have a single room when she had to go to the hospital), but the focal point was always mercy -- God’s desire to give it, humanity’s need for it, and the methods by which it could be obtained."
--"A Saint Despite Vatican Reservations,"  by John Allen, NCR Online, August 30, 2002.
It is hard for some to think of Jesus or Mary making the promises, threats, and demands visionaries claim they make. It is hard to believe they provide instructions for images they want painted or medals they want struck. Their private revelations are so unlike their gospel revelations.
"I desire that there be a Feast of Mercy. I want this Image, which you will paint with a brush, to be solemnly blessed on the first Sunday after Easter; that Sunday is to be the Feast of Mercy."
--quoted in The Life of Faustina Kowalska,  by Sister Sophia Michalenko, Marian Press, 1987, page 44.
Click here  for St. Faustina's Diary: Divine Mercy in My Soul. There is no Look Inside feature.
Click here  for Wikipedia.
It may be that the devotion to St. Faustina and to the Divine Mercy, as promulgated by Bl. John Paul II will not stand the test of time. There seem to be no new editions of the diary and no scholarly studies.