Physical
The heart. It’s a muscular organ about the size of a fist. Not very big to control a life, yet it pumps life-giving blood through a network of arteries and veins, throughout the body. If a part of the body is cut off from that blood supply, it withers and dies. An unhealthy heart causes the whole body to suffer.

Health professionals emphasize keeping our heart healthy. Each visit to my general practitioner involves him listening to my heart to make sure it’s working properly. Obviously, the heart is very important to me well-being.

Emotional

If we listen to music, poetry, and almost any television program or movie, we hear that the heart is equally important to emotional life.
Personal lives revolve around heart. We say something touches our heart. We are broken hearted or our heart is full.

The Beatles sang of a Lonely Hearts Club. Billy Ray Cyrus sang of the Achy Breaky Heart Judy Garland sang Zing! Went the Strings of My Heart We've heard Heart and Soul by many artists.

Spiritual
"And you shall love the Lord your God with all your heart and with all your soul and with all your mind and with all your strength" Mark 12:30 ESV

According to the Bible, my heart is even more important to God than it is to my doctor.
Scripture contains warnings that encourage us to pay attention and protect what we allow into our heart.

Proverbs 4:23 “Keep your heart with all vigilance, (watch over it) for from it flow the springs of life.”

Left to its own, the human heart is deceitful, and sick. We can't know its secret motives. (from Jeremiah 17:9)

Jesus taught in Luke 6:45 that the heart is a treasure trove. From a good heart a person brings out what is good and honorable and moral. But from an evil heart he produces only evil. We can see and hear the difference because “out of the overflow of the heart his mouth speaks.”

So what do we do?
We can try to control the contents of our heart. We can try to change what controls us. We can try to do better, to act and to look good. We can put up a good front.

We may even fool those around us. 1 Samuel 16:7 reminds us that we humans look at appearance and are fooled. God sees all the way to the heart. He is never fooled, for he searches and examines the heart, and tests the mind. (from Jeremiah 17:10)

We can work hard at it, but only God can change the heart of a person.

In Ezekiel 11:19 and 36.26 God promised to remove a heart of stone and give a new heart of flesh a heart that will respond to his touch.

The psalmist, in Psalm 51:10, asks God to create within him a clean heart. And to renew a right and steadfast spirit in him.


2 Corinthians 5:17 ESV “Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold the new has come."

Romans 10:9-10 teaches that with the heart we believe and are justified.

A healthy heart muscle is vital to this life. How much more a healthy spiritual heart. It guides us in this life and the next—eternally. This changed heart is important.