'Heart' in the Bible

so the king said to me, “Why are you sad, when you aren’t sick? This is nothing but depression.”I was overwhelmed with fear

I got up at night and took a few men with me. I didn’t tell anyone what my God had laid on my heart to do for Jerusalem. The only animal I took was the one I was riding.

You found his heart faithful in Your sight,and made a covenant with himto give the land of the Canaanites,Hittites, Amorites, Perizzites,Jebusites, and Girgashites—to give it to his descendants.You have kept Your promise,for You are righteous.