Concise Bible Dictionary:

The heart is often referred to in scripture as the seat of the affections and of the passions, also of wisdom and understanding—hence we read of “the wise in heart,” also the Lord gave to Solomon “a wise and understanding heart.” It is the center of a man’s being. But before the deluge God’s verdict of man was that every imagination of the thoughts of his heart was only evil continually (Gen. 6:55And God saw that the wickedness of man was great in the earth, and that every imagination of the thoughts of his heart was only evil continually. (Genesis 6:5)). A similar verdict is found in Genesis 8:2121And the Lord smelled a sweet savor; and the Lord said in his heart, I will not again curse the ground any more for man's sake; for the imagination of man's heart is evil from his youth; neither will I again smite any more every thing living, as I have done. (Genesis 8:21), after Noah came out of the ark. And the Lord said, Out of the heart of man proceed evil thoughts and every form of wickedness (Mark 7:2121For from within, out of the heart of men, proceed evil thoughts, adulteries, fornications, murders, (Mark 7:21)). The law required man to love God with all his heart. The reception of the gospel must be in the heart, (Rom. 10:99That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved. (Romans 10:9)); and God enables a hearer to receive the good news in “an honest and good heart,” upon which there is fruit (Luke 8:1515But that on the good ground are they, which in an honest and good heart, having heard the word, keep it, and bring forth fruit with patience. (Luke 8:15)). In new creation there is a “pure heart,” the Christian being led by the Holy Spirit (1 Tim. 1:55Now the end of the commandment is charity out of a pure heart, and of a good conscience, and of faith unfeigned: (1 Timothy 1:5); 2 Tim. 2:2222Flee also youthful lusts: but follow righteousness, faith, charity, peace, with them that call on the Lord out of a pure heart. (2 Timothy 2:22); 1 Pet. 1:2222Seeing ye have purified your souls in obeying the truth through the Spirit unto unfeigned love of the brethren, see that ye love one another with a pure heart fervently: (1 Peter 1:22)).

Strong’s Dictionary of Hebrew Words:

(Aramaic) corresponding to 3824
KJV Usage: