'Heart' in the Bible

To Titus, my true child in a common faith: Grace and peace [inner calm and spiritual well-being] from God the Father and Christ Jesus our Savior.

To the pure, all things are pure; but to the corrupt and unbelieving, nothing is pure; both their mind and their conscience are corrupted.

To be wise in mind, clean in heart, kind; working in their houses, living under the authority of their husbands; so that no evil may be said of the word of God.

Who gave himself for us, so that he might make us free from all wrongdoing, and make for himself a people clean in heart and on fire with good works.

For in the past we were foolish, hard in heart, turned from the true way, servants of evil desires and pleasures, living in bad feeling and envy, hated and hating one another.