Blessed Pope Pius IX, who had the longest pontificate in history after St. Peter (he reigned from 1846 to 1878), claimed “as one of his sweetest glories, his title of First Guard of Honor of the Heart of Jesus. He encouraged the Association, born under his pontificate, and enriched with indulgences the Offering Prayer of the Hour of Guard, the Precious Offering, and the monthly Billets (from the website of the Guard of Honor at Paray-le-Monial).
Pius IX was born Giovanni Maria Mastai-Ferretti in Senigallia, Italy, in what was then part of the Papal States. Not only did he approve both the worldwide devotion to the Sacred Heart and the liturgical feast, but also the foundation of the Guard of Honor of the Sacred Heart. He also convened the First Vatican Council, which decreed papal infallibility to be dogma. Blessed Pope Pius also defined the dogma of the Immaculate Conception of the Blessed Virgin Mary, meaning that Mary was conceived without the taint of original sin. In 1877 he named St. Francis de Sales a Doctor of the Church. He was the last Pope to rule the Papal States, which fell to Italian nationalist armies by 1870 and were incorporated into the Kingdom of Italy. He was beatified by St. John Paul II in 2000, together with John XXIII.
Like future Guard of Honor Pope St. John Paul II, Pius was a Marian pope. In addition to defining the dogma of the Immaculate Conception, his encyclical Ubi primum emphasized Mary’s role in salvation. He conferred the title “Our Mother of Perpetual Help” upon a Byzantine icon from Crete entrusted to the Redemptorists.
His Syllabus of Errors stands as a strong condemnation against liberalism, modernism, moral relativism, secularization, and separation of church and state, in effect definitively restating Catholic teaching regarding state recognition of the Catholic faith as the state religion in nations where the majority of the people are Catholic.