In the midst of the second world war Pope Pius XII put the whole world under the special protection of our Savior's Mother by consecrating it to her Immaculate Heart, and in 1944 he decreed that in the future the whole Church should celebrate the feast of the Immaculate Heart of Mary. This is not a new devotion. In the seventeenth century, St. John Eudes preached it together with that of the Sacred Heart; in the nineteenth century, Pius VII and Pius IX allowed several churches to celebrate a feast of the Pure Heart of Mary. Pius XII instituted today's feast of the Immaculate Heart of Mary for the whole Church, so as to obtain by her intercession "peace among nations, freedom for the Church, the conversion of sinners, the love of purity and the practice of virtue" (Decree of May 4, 1944).
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I particularly like this reflection which reminds me of why Mary was not only the first and best of Jesus' disciples, but why I should ask her for help in my own Christian journey.
The Preface of the Mass attributes a number of qualities to the Heart of Mary. It is wise, because she understood the meaning of the Scriptures as no other person had ever done, and she kept in it the memory of the words and things relating to the mystery of salvation. It is immaculate, that is, immune from any stain of sin. It is docile because she submitted so faithfully to God's will and to every one of his wishes. It is new, according to the ancient prophecy of Ezechiel -- a new heart I will give you, and a new spirit -- clothed in the newness of grae merited by Christ. It is humble because she imitated the humility of Christ, who said Learn from me; for I am gentle and lowly in heart. It is simple, free from any duplicity and full of the Spirit of truth. It is clean and thus able to see God according to the words of the Beatitude. It is firm in her acceptance of the Will of God when Simeon announced to her that a sword of sorrow would pierce her heart, when persecution broke out aginst her Son or when the moment of his death was a hand. It is ready, for whilst Christ slept in the sepulchre she kept watchin the expectation of his resurrection, just like the spouse in the Canticle of Canticles.
As we consider the splendour and holiness of the Immaculate Heart of Mary, we can examine today the depths of our own soul: whether we are open and docile to the graces and inspirations of the Holy Spirit, whether we jealously guard our heart from anything that could separate it form God, whether we pull up by the roots our little feelings of resentment, of envy ... which tend to bed themselves down within it. We know that from our heart's richness or its poverty our words and deeds will speak. The good man out of his good treasure brings forth good things. (Matt. 12:35)