O sweetest Jesus, whose overflowing charity towards men is most ungratefully repaid by such great forgetfulness, neglect and contempt, see, prostrate before Thy altars, we strive by special honor to make amends for the wicked coldness of men and the contumely with which Thy most loving Heart is everywhere treated. At the same time, mindful of the fact that we too have sometimes not been free from unworthiness, and moved therefore with most vehement sorrow, in the first place we implore Thy mercy on us, being prepared by voluntary expiation to make amends for the sins we have ourselves committed, and also for the sins of those who wander far from the way of salvation, whether because, being obstinate in their unbelief, they refuse to follow Thee as their shepherd and leader, or because, spurning the promises of their Baptism, they have cast off the most sweet yoke of Thy law.

We now endeavor to expiate all these lamentable crimes together, and it is also our purpose to make amends for each one of them severally: for the want of modesty in life and dress, for impurities, for so many snares set for the minds of the innocent, for the violation of feast days, for the horrid blasphemies against Thee and Thy saints, for the insults offered to Thy Vicar and to the priestly order, for the neglect of the Sacrament of Divine love or its profanation by horrible sacrileges, and lastly for the public sins of nations which resist the rights and the teaching authority of the Church which Thou hast instituted. Would that we could wash away these crimes with our own blood! And now, to make amends for the outrage offered to the Divine honor, we offer to Thee the same satisfaction which Thou didst once offer to Thy Father on the Cross and which Thou dost continually renew on our altars, we offer this conjoined with the expiations of the Virgin Mother and of all the Saints, and of all pious Christians, promising from our heart that so far as in us lies, with the help of Thy grace, we will make amends for our own past sins, and for the sins of others, and for the neglect of Thy boundless love, by firm faith, by a pure way of life, and by a perfect observance of the Gospel law, especially that of charity; we will also strive with all our strength to prevent injuries being offered to Thee, and gather as many as we can to become Thy followers. Receive, we beseech Thee, O most benign Jesus, by the intercession of the Blessed Virgin Mary, the Reparatress, the voluntary homage of this expiation, and vouchsafe, by that great gift of final perseverance, to keep us most faithful until death in our duty and in Thy service, so that at length we may all come to that fatherland, where Thou with the Father and the Holy Ghost livest and reignest God for ever and ever. Amen.

~ Pope Pius XI, Encyclical Letter Miserentissimus Redemptor, 1928

Devotion to the Sacred Heart of Jesus was particularly widespread in the past two centuries owing to visions received by a holy sister regarding in particular the nine First Fridays devotion. June is the month dedicating to honoring the Sacred Heart.