'Heart' in the Bible

Grace to you and peace [inner calm and spiritual well-being] from God our Father and the Lord Jesus Christ.

Even as it is meet for me to think this of you all, because I have you in my heart; inasmuch as both in my bonds, and in the defence and confirmation of the gospel, ye all are partakers of my grace.

And most of the brothers in the Lord, taking heart because of my chains, are all the stronger to give the word of God without fear.

Though some are preaching Christ out of envy and competition, others do it out of a good heart:

Because his heart was with you all, and he was greatly troubled because you had news that he was ill: