From Canterbury Tales by Taylor Taylor Marshall:
Why do Catholics have devotion to the Sacred Heart of Jesus and the Immaculate Heart of Mary? I call this “cordial devotion” (from the Latin cor, cordis meaning “heart”). English words such as “cordially” mean “heartfelt,” and our word “core” meaning “center” also comes from this Latin word.
What Does the Heart Signify?
The human heart is considered to be the symbolic center of the person and as such is signifies the will. When we are excited or scared our heartbeat rises. In times of stress or sorrow, we can feel a pain in our chest.
In the Old Testament and in Hebrew idiom, the “heart” (Hebrew: leb) is often used as a synonym for the “soul.” For example:
“My heart is troubled, my strength hath left me, and the light of my eyes itself is not with me.” (Psalm 37:11, D-R)
In fact, most languages parallel this usage. Now don’t think that ancient people were entirely ignorant of human anatomy. They new full well that the heart was a vital organ responsible for human animation. For example:
“But early in the morning, when Nabal had digested his wine, his wife told him these words, and his heart died within him, and he became as a stone.” (1 Samuel 25:37, D-R)
In Hebrew, the heart also signifies the human conscience. For example, the heart “smites” David (2 Sam 24:5). Likewise in the New Testament, as in 1 Jn 3:20, where the Apostle speaks about “whenever our hearts condemn us.” Thus, the heart functions as the seat of the moral life. This is why the Bible is so fond of the phrase “pure of heart” (Hebrew: bar lebab). Moreover, the natural law is “written on our hearts” (Rom 2:15).
Is “Heart Devotion” Biblical?
The answer here.