On August 1, 1925, Helena Kowalska was accepted to the convent of the Sisters of Our Lady of Mercy at Żytnia street in Warsaw. She later became St. Faustina. She described this day in her Diary: “At last the time came when the door of the convent was opened for me – it was the firstof August , in the evening, the vigil [of the feast] of Our Lady of the Angels. I felt immensely happy; it seemed to me that I had stepped into the life of Paradise. A single prayer was bursting forth from my heart, one of thanksgiving” (Diary, 17). On this occasion, Mass for the intention of thanksgiving for the gift of the life of the Apostle of Divine Mercy, her vocation to the consecrated life in the Congregation of the Sisters of Our Lady of Mercy charism and proclamation of the message of Mercy to the world will be celebrated, among others, at the Shrine of Divine Mercy. Because of this gift, the Congregation has considered her to be its spiritual co-founder.