'Heart' in the Bible

and it shall be to you for a fringe, that you may look on it, and remember all the commandments of Yahweh, and do them; and that you not follow after your own heart and your own eyes, after which you use to play the prostitute;

Why do you discourage the heart of the children of Israel from going over into the land which Yahweh has given them?

For when they went up to the valley of Eshcol, and saw the land, they discouraged the heart of the children of Israel, that they should not go into the land which Yahweh had given them.