
Kowalska reported a number of apparitions during religious ecstasy which she described in her 1934–1938 diary, later published as the book Diary: Divine Mercy in My Soul.

In February 1931, in Płock, Kowalska had a vision of Jesus who tasked her with spreading the devotion to His Divine Mercy. Kowalska was granted the title "Secretary of Mercy" by the Holy See in the Jubilee Year of 2000. The venerated image under this Christological title refers to what Kowalska's diary describes as "God's loving mercy" towards all people, especially for sinners. In Catholicism, Divine Mercy is a devotion to Jesus Christ associated with the reported apparitions of Jesus to Faustina Kowalska.

Catholicism Devotion Ī permanent chapel dedicated to Faustina Kowalska, within the Basilica of the Divine Mercy in Kraków, Poland In the Sermon on the Mount, Jesus said of the merciful that they will receive mercy from God and gave examples in the parable of the Good Samaritan and the parable of the Unforgiving Servant. The Hebrew word rah'amim ( Hebrew: רחמים) denotes an act of grace based on trust, in a mutual relationship between two people who have obligations to fulfill resulting from their commitments.

The term and concept of divine mercy is from the Hebrew word chesed ( Hebrew: חֶסֶד), which in the Bible can be translated as "great mercy", "goodness", "loving-kindness", "steadfast love", " covenant " faithfulness", "favor", " grace" or "love and mercy", and which refers to God's love for the Children of Israel and for all of humankind.
