[4] During her life, she reported several apparitions of the Blessed Virgin Mary and Jesus Christ through which she purportedly received prophecies about the end of the world, the Great Catholic Monarch, punishment for the sins of the people, the destruction of Paris through civil war, the Three Days of Darkness, and the coming of the Antichrist.

Marie-Julie predicted numerous chastisements for sin that would fall first on France then spread to the rest of the world.

These include: earthquakes, unprecedented destruction through storms, failed harvests, unknown plagues that would spread rapidly plus the cures for them, a "Blood Rain" that would fall for seven weeks, civil war in France that apparently would be started by conspirators in the government, the persecution of the Catholic Church with the total closure of all churches and religious houses, persecution and slaughter of Christians, the destruction of Paris, a Two Day period of Darkness that would come circa a month before the Three Days of Darkness.

In her apparitions, Jahenny was told to promote a Purple Scapular, which was to be displayed in homes and worn to provide protection during the End Times and the Three Days of Darkness.

In the Palmarian Catholic Church, based in El Palmar de Troya, Andalusia, Spain, Marie-Julie Jahenny is celebrated as a canonised saint, having been canonised by the Palmarian Holy See on 17 September 1978 in the Fourteenth Papal Document of Pope Gregory XVII.