Here is a moving prayer by Princess Élisabeth:
Adorable heart of Jesus, sanctuary of the love that led God to make himself man, to sacrifice his life for our salvation, and to make of his body the food of our souls: in gratitude for that infinite charity I give you my heart, and with it all that I possess in this world, all that I am, all that I shall do, all that I shall suffer. But, my God, may this heart, I implore you, be no longer unworthy of you; make it like unto yourself; surround it with your thorns and close its entrance to all ill-regulated affections; set there your cross, make it feel its worth, make it willing to love it. Kindle it with your divine flame. May it burn for your glory; may it be all yours, when you have done what you will with it. You are its consolation in its troubles, the remedy of its ills, its strength and refuge in temptation, its hope during life, its haven in death. I ask you, O heart so loving, the same favour for my companions. So be it.
O divine heart of Jesus! I love you, I adore you, I invoke you, with my companions, for all the days of my life, but especially for the hour of my death.
O vere adorator et unice amator Dei, miserere nobis. Amen.