Under this title, a book by Sr. Miriam Janiec from the Congregation of the Sisters of Our Lady of Mercy has been published by the Misericordia publishing company as another manual for the first year of formation in the Faustinum Association of Apostles of Divine Mercy. The Author states in the Introduction: Let My mercy work in you, in your poor soul (Diary, 1486). These are the words that Jesus addresses to each one of us today, because He wishes to lead us along paths of trust and mercy until we are completely conformed to Him, as He had His beloved Daughter. If you feel that this is your path, if you are drawn to and fascinated by the mystery of God’s mercy, or if you simply want to know it better, I invite you to join me on this journey together with the Apostle of Divine Mercy. The book is accompanied by a workbook with exercises for each topic discussed. It is intended to help you make a personal commitment to formation in Sister Faustina’s school of spirituality. The book is available for purchase at the shop of the Misericordia publishing company and at the secretariat of the Faustinum Association of Apostles of Divine Mercy at the Łagiewniki Shrine.