Heart
The heart means love. A good heart means love to the Lord and to the neighbor, while a hard or stony heart means the love of self or the world -- riches and things. When the psalmist asks the Lord to search his heart, he wants the Lord to see what it is that he loves. And we are what we love. What we eat may form our earthly body, but it's only temporary, what we love forms our spiritual body, beautiful or ugly as we have chosen. It's interesting to note that the first multi-cellular motion of our embryo is the pulsating that starts in a twist of blood vessel that is to become our heart, and the last motion of our natural body is our heartbeat. It is there for all of our natural life. And of course there is a beating heart in our spiritual bodies when we come to put them on.
Jeremiah 31:31-33
31
Behold, the days come, says Yahweh, that I will make a new covenant with the house of Israel, and with the house of Judah:
32
not according to the covenant that I made with their fathers in the day that I took them by the hand to bring them out of the land of Egypt; which my covenant they broke, although I was a husband to them, says Yahweh.
33
But this is the covenant that I will make with the house of Israel after those days, says Yahweh: I will put my law in their inward parts, and in their heart will I write it; and I will be their God, and they shall be my people:
