'Heart' in the Bible

On the seventh day, when the king's heart was merry with wine, he commanded Mehuman, Biztha, Harbona, Bigtha, and Abagtha, Zethar, and Carcas, the seven chamberlains that served in the presence of king Ahasuerus,

And Mordecai bade to answer Esther: Imagine not in thy heart that thou shalt escape in the king's house, more than all the Jews.

And Haman went forth that day joyful and glad of heart; but when Haman saw Mordecai in the king's gate, that he stood not up nor moved for him, he was full of fury against Mordecai.

So Haman came in. And the king said to him, What is to be done with the man whom the king delights to honour? Now Haman thought in his heart, To whom would the king delight to do honour more than to me?

And king Ahasuerus spoke and said to Esther the queen, Who is he, and where is he that has filled his heart to do so?