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.

7542. 'Onto your heart' means into what is inmost. This is clear from the meaning of 'heart' as that which belongs to a person's will, thus to his love, dealt with in 2930, 3317, 3888, 3889, consequently what is central to the actual life within him; for his love, belonging intrinsically to his will, constitutes that life within him. This is why 'heart' means what is inmost. What is inmost in the case of the good is love to the Lord and love towards the neighbour, whereas what is inmost in the case of the evil is self-love and love of the world. The latter is what is meant here; and what is around it, constituting so to speak the surrounding parts, are the evils and falsities that lend support, arranged into order according to the ways in which they support it. In the next life they are brought out into the open in the order in which they have been arranged. First to come forth are those that occupy the outermost surrounding parts, then those that lie further in; and finally what is inmost is revealed. So it is that a person in the next life passes through a large number of states, and that the evil are afflicted in successive stages by scourges or plagues before they are cast into hell, as accords with what has been stated immediately above. What is inmost, which they come to last of all, is hell itself residing with them, for it is the evil that had been central to their love, and so the end which they held in view in everything they did and which in the world they had kept deeply hidden within them.