60 The eternal Son of God, in his utter transcendence, chose to love each of us with a human heart. His human emotions became the sacrament of that infinite and endless love. His heart, then, is not merely a symbol for some disembodied spiritual truth. In gazing upon the Lord’s heart, we contemplate a physical reality, his human flesh, which enables him to possess genuine human emotions and feelings, like ourselves, albeit fully transformed by his divine love. Our devotion must ascend to the infinite love of the Person of the Son of God, yet we need to keep in mind that his divine love is inseparable from his human love. The image of his heart of flesh helps us to do precisely this.
Source: Dilexit Nos (Vatican.va)