The Diary of Saint Faustina Kowalska (original title: “Divine Mercy in My Soul”) is today considered one of the most important mystical texts in the history of the Church. However, few know that this masterpiece of spirituality was born under the sign of obedience and had to overcome terrible trials, including demonic temptations and the physical destruction of the first manuscripts.
The Origin: An Order from Heaven and Earth
Sister Faustina, a simple Polish nun with minimal education, never thought she would become a writer. It was Jesus Himself who asked her to record His messages:
“Secretary of My most profound mystery, your task is to write down everything I make known to you about My Mercy.” (Diary, 1605)
However, it was her spiritual director in Vilnius, Blessed Michael Sopoćko, who gave her the formal order to write. Concerned that their spiritual direction sessions in the confessional were taking too much time, he ordered her to put everything in writing so that he could read it calmly and carefully discern the nature of these revelations.
The Demon’s Deception and the Destruction of the Diary
The history of the Diary is marked by a dramatic episode that occurred in 1934. While Fr. Sopoćko was away from Vilnius, Sister Faustina had a vision: a being appearing as an Angel of Light ordered her to burn the manuscript, claiming that what was written was merely a product of fantasy or vanity, and that by destroying it, she would perform an act of humility.
In reality, it was not an angel, but a demon in disguise. In a moment of terrible spiritual trial, convinced she was fulfilling God’s will, Faustina threw the pages into the fire, reducing months of heavenly dialogues to ashes.

Saint Faustina’s small house in Vilnius. Inside, the original stove where the Saint burned the manuscript is still present.
Fr. Sopoćko’s Command: Starting from Scratch
Upon his return, Fr. Sopoćko was shocked to discover that the manuscripts had been lost. To test the saint’s obedience and recover those spiritual treasures, he gave her a very hard penance: rewrite everything from the beginning.
This is why the Diary, in its current form, has a particular structure. The first part contains past memories written from memory, while the subsequent parts follow a daily chronological order. This immense effort, carried out by a woman gravely ill with tuberculosis and often mocked by others, is tangible proof of her total love for the mission entrusted to her.

Diary of Saint Faustina
Spiritual Importance: Why Read the Diary Today?
Reading Saint Faustina’s Diary does not just mean deepening your knowledge of a mystic’s life; it means entering into a direct conversation with God. Jesus Himself explained to Faustina that His words in the Diary are meant to give hope to discouraged souls:
“In it, weary souls will find comfort, doubting souls relief, and those who succumb, strength” (Diary, 1521).
The spiritual importance of this work lies in its ability to break down the barriers of fear. In an era marked by anxiety, the Diary serves as a “Gospel of Mercy,” reminding us that no sin is greater than God’s capacity to forgive. Reading even a small passage every day helps to:
- Cultivate Trust: Abandon yourself like a child into the Father’s arms.
- Transform Suffering: Understand how to offer your own pain for the salvation of the world.
- Live Charity: Become witnesses of mercy to our neighbors.
What Does the Diary Contain?
The text is divided into six notebooks. It is not a traditional autobiography, but an unceasing dialogue between the soul and the Creator. It contains the foundations of modern devotion:
- Instructions for the Image of the Divine Mercy.
- Explanation of the Feast of Mercy.
- Promises related to the Chaplet.
- Prophetic visions regarding the destiny of the world and the Church.
A Digital Tool for Your Prayer
For those who wish to always have the most significant passages and the Novena texts from the Diary with them, we remind you that our Free Android App is available. It is the ideal tool for those who want to meditate on Jesus’ words to Saint Faustina at any time of the day, turning your smartphone into a compass for the soul.
Free Download: Diary of Saint Faustina in English
From the following link, you can download the PDF of Saint Faustina’s Diary in English for free. The PDF is not released by us and is not hosted on our site.