Jeremiah’s Teaching on Man’s Heart
March 28, 2022
David Cloud, Way of Life Literature, P.O. Box 610368, Port Huron, MI 48061

The following is excerpted from The Way of Life Commentary Series, Jeremiah, 

Jeremiah 17:9-10 “The heart is deceitful above all things, and desperately wicked: who can know it? I the LORD search the heart, I try the reins, even to give every man according to his ways, and according to the fruit of his doings.”

This is one of the most important passages in Scripture about the condition of man’s heart. Every word is instructive.

1. Man’s heart is deceitful above all things (Jer. 17:9).

- Man’s fallen heart is a lying heart. The Hebrew word for deceitful is “aquob” (aw-kobe) which refers to cheating, crookedness. The prime root, “aqab,” is translated “supplant,” referring to Jacob’s deceitful actions toward Esau (Ge. 27:36). Jacob’s very name means “supplanter” or “heel catcher” (Ho. 12:3). That is Jacob by nature apart from God’s redemption. “Aquob” is also translated “crooked” (Isa. 40:4) and “polluted” (Ho. 6:8). The very essence of man’s fallen nature is deceit. The word “deceive” in its various forms appears 79 times in Scripture, which does not include associated terms such as “lying,” “slander,” “supplant,” and “dealing falsely.” Man deceives others and he deceives himself -- “deceiving, and being deceived” (2 Ti. 3:13). The lying begins at birth. “The wicked are estranged from the womb: they go astray as soon as they be born, speaking lies” (Ps. 58:3). No parent has to send a child to a school to learn to lie. For fallen mankind, lying is as natural as breathing. We lie in a thousand ways: by speaking lies, by not speaking the truth, by not speaking the whole truth, by not being open and candid as a Nathanael (Joh. 1:47), by hypocrisy, by cheating, by evil manipulation. 

- The fact that the human heart is deceitful explains why the world is full of lies and truth is rare. Lies permeate every facet of human society: politics, the news media, historical studies, sociology, anthropology, philosophy, ethics, religion, psychology, origins, economics. 

- Jeremiah 17:9 is one of the verses that God used to bring light and conviction to me when I was lost and to bring me to salvation. This is the verse that a man used repeatedly in 1973 to show me my sin. We met while traveling and had a multi-day conversation that resulted in my conversion. One of the first things I said to him was, “I am trusting in my heart; I am following my heart.” He replied, “The Bible says, ‘The heart is deceitful above all things, and desperately wicked: who can know it?’” He opened his Bible and showed me the verse. I was amazed. I grew up in church, but I don’t recall being taught this truth. I thought the Bible was just a bunch of old stories that had no relevance to my daily life. I was amazed at how the Bible described man’s condition in such a clear and practical way. That is one of the major verses that removed my trust in self and caused me to trust in the Lord. 

- After I was saved, Jeremiah 17:9 continued to help me not to trust in myself when I was seeking to understand the Bible properly and to interpret it in a right way and to find my way through the doctrinal wilderness of modern Christianity. I was confronted with Pentecostalism and Mormonism and Seventh-day Adventism and Armstrongism. I would literally cry out, “Lord, I know that a man can deceive himself; don’t let me be deceived; if in any way I am being deceived, show me.” 

2. Man’s heart is desperately wicked (Jer. 17:9).

- Man’s heart is not only deceitful, it is desperately wicked. It is terribly wicked. It is foul. All of man’s sinful actions flow from his wicked heart. As Jesus said, “For from within, out of the heart of men, proceed evil thoughts, adulteries, fornications, murders, thefts, covetousness, wickedness, deceit, lasciviousness, an evil eye, blasphemy, pride, foolishness: All these evil things come from within, and defile the man” (Mr. 7:21-23). 

3. Man’s heart is unknowable (“who can know it?” Jer. 17:9). 

- Man cannot know his own heart. Man tries to understand himself by psychology and philosophy, but it is in vain. Man must have divine help. Who can know man’s heart? God can! The Spirit of God and the Word of God will reveal the true condition of man’s heart. “For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart” (Heb. 4:12). This is what happened to me at age 23 when I was confronted by a wise soul winner who opened God’s Word and shed light upon my deceitful, wicked heart, and the Spirit of God enlightened me to my true condition and pointed me to Christ. 

- The way of wise Christian living is to refuse to trust one’s own heart, one’s own thinking, one’s own emotions, and to cast oneself exclusively upon God and His Word. I must search the Word daily and meditate therein day and night so that I can go in the way of truth and not in the way of my own heart. “Trust in the LORD with all thine heart; and lean not unto thine own understanding. In all thy ways acknowledge him, and he shall direct thy paths” (Pr. 3:5-6). “Sanctify them through thy truth: thy word is truth” (Joh. 17:17).

4. Man’s heart is searched by God (Jer. 17:10). 

- God searches every man’s heart. Men think they can live independently of God, but that is impossible. Man can live in disobedience to God and as a rebel to God for a brief time in this present world, but no man can live independently of God. Not only do we get our very life and breath from Him, but He searches every man’s heart. He knows every man’s thoughts and deepest secrets.  

- We see God’s breathtaking omniscience. He knows the thoughts of every one of the billions upon billions of men, women, and children who have ever lived. He “seeest the reins and the heart” (Jer. 20:12). He searches all hearts (1 Ch. 28:9). He alone knows the hearts of man (2 Ch. 6:30). All things are naked and open before Him (Heb. 4:13). Our secret sins are before Him (Ps. 90:8).

- Since God knows the heart, He can show a man his true condition if the individual will look to him for help and not trust himself. The wise individual will constantly cast himself in dependence upon God to search him and to reveal the secrets of his own heart that he might walk in repentance and obedience and truth. David showed the way when he said, “Search me, O God, and know my heart: try me, and know my thoughts: And see if there be any wicked way in me, and lead me in the way everlasting” (Ps. 139:23-24), and, “Examine me, O LORD, and prove me: try my reins and my heart” (Ps. 26:2).

- God judges every man. Man is accountable to God for every thought and deed, and every man and woman will give account, either at the judgment seat of Christ, for those who are saved (1 Co. 3:13-15; 2 Co. 5:10), or at the Great White Throne, for those who die without the Saviour (Re. 20:11-15). Jesus warned that “every idle word that men shall speak, they shall give account thereof in the day of judgment” (Mt. 12:36). God will “bring to light the hidden things of darkness, and will make manifest the counsels of the heart” (1 Co. 4:5). That which has been spoken in darkness will be heard in the light (Lu. 12:3).

5. Jesus Christ is the only man since Adam who was born with a pure heart. 

- Due to the virgin birth, Christ did not inherit the fallen sin nature from Adam. Christ is holy and undefiled (Heb. 7:26). He did no sin, neither was guile found in His mouth (1 Pe. 2:22). He is without sin (Heb. 4:15). In Him is no sin (1 Jo. 3:5). He knew no sin (2 Co. 5:21).

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