'Heart' in the Bible

But because of your stubbornness and unrepentant heart, you are storing up for yourself wrath in the day of wrath and of the revelation of the righteous judgment of God,

But the Jew {is one inwardly}, and circumcision [is] of the heart, by the Spirit, not by the letter, whose praise [is] not from people but from God.

But thanks [be] to God that you were slaves of sin, but you have obeyed from the heart the pattern of teaching to which you were entrusted,

that my grief is great and [there is] constant distress in my heart.

Brothers, the desire of my heart and my prayer to God on behalf of them [is] for [their] salvation.

But the righteousness from faith speaks like this: "Do not say in your heart, 'Who will ascend into heaven?'" (that is, to bring Christ down),

But what does it say? "The word is near to you, in your mouth and in your heart" (that is, the word of faith that we proclaim),

that if you confess with your mouth "Jesus [is] Lord" and believe in your heart that God raised him from the dead, you will be saved.

For with the heart one believes, resulting in righteousness, and with the mouth one confesses, resulting in salvation.