"Do not store up for yourselves treasures on earth, where moth and rust consume and where thieves break in and steal; but store up for yourselves treasures in heaven, where neither moth nor rust consumes and where thieves do not break in and steal. For where your treasure is, there your heart will be also" (Mt. 6:19-21 NRSV).
COMMENT: I've added to your request the preceding two verses, so that we can appreciate the entire thought. This is, of course, from the Sermon on the Mount. Jesus is speaking to his closest followers, trying to explain what his ministry is – and is not – about. His constant theme – introduced here and repeated throughout his ministry – is that his message is not about the things of this world. It is about a new consciousness that transcends this world – a consciousness that is as eternal as this world is temporal. He describes this consciousness as the “kingdom of heaven,” and it must have sometimes been frustrating to try to explain how immeasurably richer and more meaningful it is than any worldly distractions could ever be.
Metaphysically, the heart is a center of love, yes, but also of faith. It is symbolically that place within where we most clearly feel our Oneness with God. From that perfect heart perspective, the only important question is: Where is your treasure? What do you value? What is important to you? If your response is that you are still obsessed with the things of this world, then any sense of achievement will be short-lived at best. If what you value, what you truly want is to live in the peace, abundance and love of God, then achieving that will be the pleasure of your heart energy. The choice is ours. Making a “treasure” out of earthly distractions may seem appealing, but it won't last. Declaring a “treasure” that is spiritual in nature and centered in love will result in absolute and endless joy.