Maria Pierina De Micheli was born on September 11, 1890 in Milan as Giuseppa Maria in a deeply religious family. At the age of 11 she experienced the first revelation – on Good Friday in her parish church she heard a voice: Will no one kiss me with love, to reward me for the kiss of Judas? Then the girl, not understanding much, kissed the cross with the greatest concern.
On October 15, 1913, Giuseppa joined the Congregation of Daughters of the Immaculate Conception, and on May 16, 1914, she received the habit and took the name Maria Pierina. A year later she made her religious vows. In 1919 she went to Argentina with several other Sisters. There, at the Congregational home in Buenos Aires, in 1921 she made her perpetual vows. As before, in Italy, she spent many hours meditating and adoring the Passion of the Lord, especially the Face of Jesus, which was the main source of her reflections and thoughts. In 1921 she returned to her homeland. In 1928 she became the superior of the house in Milan and then – the delegate of the Superior General for external affairs. Despite these administrative duties, she deeply lived the mystical experiences.