Désiré Félicien François Joseph Cardinal Mercier (21 November 1851 – 23 January 1926) was a Belgian cardinal of the Catholic Church and a noted scholar. A Thomist scholar, he had several of his works translated into other European languages. He was known for his book, Les origines de la psychologie contemporaine (1897). His scholarship gained him recognition from the Pope and he was appointed as Archbishop of Mechelen (Malines), serving from 1906 until his death, and was elevated to the cardinalate in 1907.
Mercier is noted for his staunch resistance to the German occupation of 1914–1918 during World War I.
After the invasion, he distributed a strong pastoral letter, Patriotism and Endurance, to be read in all his churches, urging the people to keep up their spirits. He served as a model of resistance.
Cardinal Mercier had a zeal that issued from a love of doctrinal truth. In the wartime chaos of 1917, he told his priests not to tell their people to love if they could not explain the theology that justifies love. He gave a practical formula for happiness:
"Every day for five minutes control your imagination and close your eyes to the things of sense and your ears to all the noises of the world, in order to enter into yourself. Then, in the sanctity of your baptized soul (which is the temple of the Holy Spirit), speak to that Divine Spirit, saying to Him:
O Holy Spirit, beloved of my soul, I adore You. Enlighten me, guide me, strengthen me, console me. Tell me what I should do. Give me your orders. I promise to submit myself to all that You desire of me and accept all that You permit to happen to me. Let me only know Your Will.
If you do this, your life will flow along happily, serenely, and full of consolation, even in the midst of trials. Grace will be proportioned to the trial, giving you strength to carry it, and you will arrive at the Gate of Paradise laden with merit."
May we take the valuable, practical advice of Cardinal Mercier to heart in our daily quest to live out our vocational call to holiness.
Sources: Cardinal Mercier, hero to the world (catholiceducation.org) and Désiré-Joseph Mercier - Wikipedia