The happiest day of St. John Paul II’s life according to him was the day he canonized St. Faustina, a nun from his homeland; Poland.
St. Faustina was born Helena Kowalska to a poor but devout Polish family in 1905. At the age of 20, with very little education, and having been rejected from several other convents because of her poverty and lack of education, Helen entered the Congregation of the Sisters of Our Lady of Mercy. There, she took the name Sr. Faustina and spent time in convents in both Poland and Lithuania.
Throughout her life, Faustina reported having visions of Jesus and conversations with him, of which she wrote in her diary, later published as The Diary of Saint Maria Faustina Kowalska: Divine Mercy in My Soul. Jesus also asked Sr. Faustina to have an image painted of his Divine Mercy, with red and white rays issuing from his heart, and to spread devotion to the Divine Mercy novena.
The devotion to Divine Mercy began to spread throughout Poland, even before her death on October 5, 1938.
Although Sr. Faustina’s life overlapped with John Paul II (then Karol Wojtyla) for several years in Poland, the knowledge of St. Faustina and the revelations bestowed on her coming from Jesus became known to Pope John Paul II early in 1940. It was at the time when he was studying for the priesthood secretly, in a seminary in Krakow during World War II.
The Vatican placed a ban on spreading the devotion in the 1950s, due to an inaccurate Italian translation of the Diary of Divine Mercy and other unresolved issues, which was lifted just six months before Cardinal Karol Wojtyla became Pope John Paul II.
On the first Sunday of Advent, November 30, 1980, Pope John Paul published his second encyclical “Rich in Mercy” (Dives in Misericordia) in dedication to Divine Mercy.
Throughout his papacy, John Paul II often write or speak about the necessity of pleading for God’s Divine Mercy for the whole world. On April 19, 1993, he beatified Sr. Faustina, and in his homily he praised the way she drew many people to the merciful heart of Christ.
“It is truly marvelous how her devotion to the merciful Jesus is spreading in our contemporary world and gaining so many human hearts! This is doubtlessly a sign of the times — a sign of our twentieth century. The balance of this century, which is now ending, in addition to the advances which have often surpassed those of preceding eras, presents a deep restlessness and fear of the future. Where, if not in the Divine Mercy, can the world find refuge and the light of hope? Believers understand that perfectly”
On April 30, 2000, Pope John Paul II canonized St. Faustina in what he was widely reported as saying was “the happiest day of my life.”
In his homily on the day of canonization, Pope John II said: “Today my joy is truly great in presenting the life and witness of Sr Faustina Kowalska to the whole Church as a gift of God for our time. By divine Providence, the life of this humble daughter of Poland was completely linked with the history of the 20th century, the century we have just left behind. In fact, it was between the First and Second World Wars that Christ entrusted his message of mercy to her. Those who remember, who were witnesses and participants in the events of those years and the horrible sufferings they caused for millions of people, know well how necessary was the message of mercy.”
It was also on this day, the Sunday after Easter, that Pope John Paul II instituted the Feast of Divine Mercy, which Jesus had asked for in his messages to Sr. Faustina.
Special graces (similar to indulgence) are granted to souls on this day who receive sacramental confession and communion. Jesus promised that souls who fulfilled these requirements on this day would be returned to their pure, baptismal state, among other graces.
Jesus said to Sr. Faustina of this feast:
“I desire that the Feast of Mercy be a refuge and 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 the complete forgiveness of sins and punishment. On that day all the divine floodgates through which grace flow are opened. Let no soul fear to draw near to Me, even though its sins be as scarlet.” (Diary 699)