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.

7326. 'And they will be blood' means that they will falsify truths. This is clear from the meaning of 'blood' as the falsification of truth, dealt with above in 7317. In the genuine sense 'blood' means the holiness of love, as a consequence of which it means charity and faith, since they are holy attributes of love, and as a consequence of which again it means holy truth coming forth from the Lord, tool, 4735, 6978. In the contrary sense however 'blood' means violence done to charity and also violence done to faith, thus to holy truth coming forth from the Lord. And since violence is done to it when it is falsified the falsification of truth is meant by 'blood'; or when there is a greater degree of violence, the profanation of truth is meant by 'blood'. Such profanation was meant by 'the eating of blood', which was why that practice was so strictly forbidden, 1003.