The phrase "an abundance of the heart" is a proverb that means having an excess or surplus of something, such as kindness, generosity, or love. Full definition
May I offer that dichotomies are often reflective of the author's heart, for «out of the abundance of the heart, the mouth speaks». (nakedpastor.com)
May the words that flow from our mouths, even in matters as seemingly inconsequential as a football game, be filled with grace and wisdom — for, as the Lord reminded us in the Gospel of Luke, out of the abundance of the heart, the mouth speaks. (relevantmagazine.com)