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.

100. That 'a garden' means intelligence and 'Eden' love, is also evident in Isaiah,

Jehovah will comfort Zion, He will comfort all her waste places, and will make her wilderness like Eden and her desert like the Garden of Jehovah. Joy and gladness will be found in her, confession and the voice of song. Isaiah 51:3.

Here 'wilderness', 'joy', and 'confession' are terms used by the prophet to express the celestial things of faith, that is, things that belong to love. But 'desert', 'gladness', and 'the voice of song' express the spiritual things of faith, which in turn are matters of the understanding. The former relate to 'Eden', the latter to 'a garden'. For throughout this prophet dual expressions for the same thing are constantly occurring, with one expression meaning celestial things, the other spiritual. For more about what the garden in Eden means, see at verse 10 below.