You asked

how does the old testament concept of the 'heart' compare with paul's description of his inner struggle?

Adds the setting and its conversation across both testaments.

Jeremiah 17:9-10 & Romans 7:15, 18-19

“Jeremiah 17:9-10: "The heart is deceitful above all things, and it is exceedingly corrupt: who can know it? I, Yahweh, search the mind, I try the heart, even to give every man according to his ways, according to the fruit of his doings." Romans 7:15: "For I don’t know what I do. For what I want, that I don’t do; but what I hate, that I do." Romans 7:18-19: "For I know that in me, that is, in my flesh, dwells no good thing. For desire is present with me, but I don’t find it to do that which is good. For the good which I desire, I don’t do; but the evil which I don’t desire, that I practice."”

Jeremiah, a prophet in Judah during the 7th-6th centuries BCE, often delivered messages of judgment and hope to a people who had strayed from their covenant with God. His words here describe the inherent nature of humanity's inner being. Paul, writing to believers in Rome around 57 CE, explains the ongoing struggle with sin that even a committed follower of Christ can experience, using his own life as an example.

What does acknowledging an inner conflict mean for how we approach our decisions and our understanding of ourselves?

Then — the setting

The Old Testament concept of the 'heart' (Hebrew: *lev* or *levav*) was far broader than the modern English 'heart' which often signifies emotions. For ancient Israelites, the heart was the center of intellect, will, emotion, conscience, and moral choice. It was the totality of the inner person. Jeremiah's declaration that the heart is 'deceitful' and 'exceedingly corrupt' reflects a deep theological understanding of human fallenness and the pervasive nature of sin. This passage in Jeremiah belongs to a section where the prophet contrasts reliance on human strength with reliance on Yahweh, emphasizing that God alone can truly know the depths of human motivation and intention.

Across the Testaments

The Old Testament (represented by Jeremiah) describes a human heart that is inherently flawed and unable to fully know itself, requiring divine scrutiny. It highlights a universal human condition where intentions and actions are often at odds with God's law. Paul's description in Romans 7 echoes this profound inner brokenness. While Jeremiah diagnoses the problem of the deceitful heart, Paul experiences it personally as a tension between the 'desire' to do good (which aligns with the Law) and the 'flesh' (his sinful nature) that leads him to do what he hates. Paul's struggle is a vivid New Testament example of the Old Testament's assessment of the heart's fallen state, even within someone who is committed to God. The New Testament, particularly through Paul, then points to the Holy Spirit and Christ as the solution to this inner conflict, offering a new heart and the power to obey God (e.g., Romans 8:4-9, Ezekiel 36:26-27).

Keep thinking

Read alongside it

Proverbs 4:23
Advises guarding the heart, as it is the wellspring of life.
Matthew 15:18-19
Jesus teaches that evil thoughts and actions originate from the heart.
Galatians 5:17
Paul describes the ongoing conflict between the flesh and the Spirit within believers.

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