'Heart' in the Bible

but according as it is written, Things which eye has not seen, and ear not heard, and which have not come into man's heart, which God has prepared for them that love him,

But he who stands firm in his heart, having no need, but has authority over his own will, and has judged this in his heart to keep his own virginity, he does well.

the secrets of his heart are manifested; and thus, falling upon his face, he will do homage to God, reporting that God is indeed amongst you.