'Heart' in the Bible

And the king said to me, Why is your face sad, seeing that you are not ill? this is nothing but sorrow of heart. Then I was full of fear;

And in the night I got up, taking with me a small band of men; I said nothing to any man of what God had put into my heart to do for Jerusalem: and I had no beast with me but the one on which I was seated.

And my God put it into my heart to get together the rulers and the chiefs and the people so that they might be listed by families. And I came across a record of the names of those who came up at the first, and in it I saw these words:

You saw that his heart was true to you, and made an agreement with him to give the land of the Canaanite, the Hittite, the Amorite and the Perizzite and the Jebusite and the Girgashite, even to give it to his seed, and you have done what you said; for righteousness is yours: