'Heart' in the Bible

You will have a tassel {for you to look at} and remember all the commands of Yahweh and do them, and not follow {after the unfaithfulness of your own heart and eyes},

And Moses said, "In this you will know that Yahweh has sent me to do all these works; [it is] not from my heart.

'If Balak gave to me the fullness of his house full of silver and gold, I am not able to go beyond {the command of Yahweh} to do good or evil, from my heart; what Yahweh speaks, I will speak'?

When they went up to the valley of Eshcol and saw the land, they discouraged the heart of the {Israelites} so that they did not come to the land that Yahweh gave to them.