Désiré-Joseph Cardinal Mercier (1851-1926) was Archbishop of Malines, Belgium from 1906 until his death. Besides the heroic leadership he demonstrated during World War I, Cardinal Mercier hosted the famous Catholic-Anglican dialogue known as the Malines Conversations, and obtained the establishment of the liturgical feast of the Blessed Virgin Mary, Mediatrix of All Graces with its proper Mass and Office. His spiritual mentor was Blessed Dom Columba Marmion.
Once, when someone asked Cardinal Mercier how much time what ought to spend on prayer, he replied: Il faut donner à l’oraison autant de temps que l’on peut — One must give to prayer as much time as one can.
To someone else, he said: Ce n’est qu’après trois ou quatre heures de prière que viennent les grandes lumières, — It is only after three or four hours of prayer that the great lights come.