Rubrics
According to the original decree of 6 January 1884 that imposed the Leonine Prayers, they were to be said after every Low Mass, but later decrees, whose interpretation was not always clear, spoke rather of "private Masses", what in present-day legislation are called Masses without the people. According to one influential rubricist, the Leonine Prayers could be omitted after a Low Mass that was celebrated with special solemnity, such as an ordination or funeral Mass, a First Friday Votive Mass of the Sacred Heart, a Nuptial Mass, or the Mass after distribution of the ashes on Ash Wednesday, or if the Mass was followed immediately by function such as Benediction of the Blessed Sacrament or a Novena.
They were customarily said kneeling.
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