'Heart' in the Bible

I pray that the perception of your mind may be enlightened so you may know what is the hope of His calling, what are the glorious riches of His inheritance among the saints,

[and He did this] so that in the ages to come He might [clearly] show the immeasurable and unsurpassed riches of His grace in [His] kindness toward us in Christ Jesus [by providing for our redemption].

Therefore I ask you not to lose heart at my tribulations on your behalf, for they are your glory.

I then, the prisoner in the Lord, make this request from my heart, that you will see that your behaviour is a credit to the position which God's purpose has given you,

Having the understanding darkened, being alienated from the life of God through the ignorance that is in them, because of the blindness of their heart:

(for the fruit [the effect, the result] of the Light consists in all goodness and righteousness and truth),

Speaking to yourselves in psalms and hymns and spiritual songs, singing and making melody in your heart to the Lord;

Servants, be obedient to them that are your masters according to the flesh, with fear and trembling, in singleness of your heart, as unto Christ;

Not with eyeservice, as menpleasers; but as the servants of Christ, doing the will of God from the heart;