Heart
The human heart is the inward organ on which scripture loads almost the whole of a person's moral life. From it come thoughts, affections, will, courage, deceit, and devotion; into it Yahweh writes his law, his fear, and his name; and from its condition the visible life of the man is read. The UPDV corpus exhibits the heart as a single inward seat that bears two opposed conditions — the unregenerate or hardened heart that loves evil and resists Yahweh, and the renewed or contrite heart that fears him, knows him, and returns to him whole. Hardness can be self-inflicted or judicially confirmed. Renewal is portrayed as Yahweh's gift, an extraction of stone and an installation of flesh, paired with a new spirit deposit. Through the whole movement, Yahweh is the one who looks on the heart, tries it, and renders to every man according to what he finds there.
The Heart as Inward Seat
Before any moral verdict is pronounced, the heart is named as the place where thought, plan, speech, courage, and feeling live. It is the seat behind the face. The Preacher of Sirach makes the inward-to-outward motion explicit: "The heart of a common man will change his face; Whether for good or for evil" (Sirach 13:25), and again, "The footprint of a good heart is a bright face; But a distracted [face] tells of thoughts of trouble" (Sirach 13:26). Hannah's prayer in the temple is a heart-prayer that does not become voice — "Now Hannah, she spoke in her heart; only her lips moved, but her voice wasn't heard" (1 Sam 1:13) — and David's confession in the cave fastens the same interior at a steadied register: "My heart is fixed, O God, my heart is fixed: I will sing, yes, I will sing praises" (Ps 57:7). The heart is also the courage-seat: "all the stout of heart came together with him" at the death-battle of Elasa (1 Macc 9:14), and the psalmist exhorts, "Be strong, and let your heart take courage" (Ps 27:14).
It is this same organ that the wise are told to guard above everything else: "Keep your heart with all diligence; For out of it are the issues of life" (Prov 4:23). The plans, the speech, and the visible posture of a man trace back to it: "The plans of the heart belong to man; But the answer of the tongue is from Yahweh" (Prov 16:1). And Jeremiah insists the heart is so deeply the bearer of moral content that even Judah's sin is engraved on it: "The sin of Judah is written with a pen of iron, [and] with the point of a diamond: it is graven on the tablet of their heart" (Jer 17:1).
The Heart Yahweh Searches
Scripture treats the heart as the one organ that is opaque to other men and transparent to Yahweh. The line is drawn at Samuel's anointing of David: "for [it is] not [a matter of] what man sees; for man looks on the outward appearance, but Yahweh looks on the heart" (1 Sam 16:7). Solomon's dedication prayer fastens that uniqueness explicitly: "for you, even you only, know the hearts of all the sons of man" (1 Kings 8:39). The same divine prerogative is the testing-claim of Yahweh in the prophets — "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" (Jer 17:10) — and in the Psalter: "the righteous God tries the minds and hearts" (Ps 7:9); "Try my heart and my mind" (Ps 26:2); "Search me, O God, and know my heart: Try me, and know my thoughts" (Ps 139:23). The wisdom verdict is the same: "The refining pot is for silver, and the furnace for gold; But Yahweh tries the hearts" (Prov 17:3).
Heart-knowledge stays divine into the New Testament. Apostolic preaching assumes it — "we speak; not as pleasing men, but God who proves our hearts" (1 Thess 2:4) — and the risen Christ in the Apocalypse claims it under his own name: "all the churches will know that I am he who searches the minds and hearts: and I will give to each one of you⁺ according to your⁺ works" (Rev 2:23). The cutting agent of that searching is named in Hebrews: the word of God is "able to discern the thoughts and intents of the heart" (Heb 4:12). Solomon's charge to his son holds the two halves together — divine search and human seeking — in one breath: "serve him with a perfect heart and with a willing soul; for Yahweh searches all hearts, and understands all the imaginations of the thoughts: if you seek him, he will be found of you" (1 Chron 28:9).
The Unregenerate Heart
The diagnosis under which scripture sets the human heart in its native condition is grim and largely uniform. Genesis registers it twice in the flood narrative: "every imagination of the thoughts of his heart was only evil continually" (Gen 6:5); "the imagination of man's heart is evil from his youth" (Gen 8:21). Jeremiah's verdict tightens the language: "The heart is deceitful above all things, and it is exceedingly corrupt: who can know it?" (Jer 17:9). The Preacher fastens the same content at universal scope — "the heart of the sons of man is full of evil, and madness is in their heart while they live" (Eccl 9:3) — and traces a corruption mechanism by which delayed judicial sentence consolidates inward evil: "Because sentence against an evil work is not executed speedily, therefore the heart of the sons of man is fully set in them to do evil" (Eccl 8:11). Wisdom registers the same indictment in proverbial form: "Who can say, I have made my heart clean, I am pure from my sin?" (Prov 20:9); "In whose heart is perverseness, Who devises evil continually" (Prov 6:14).
The Gospel and the apostle take the same line. Out of the heart of men proceed "evil thoughts ... whoring, thefts, murders, adulteries" (Mark 7:21), and Paul's Romans diagnosis fastens its darkening as the inward consequence of refused worship: "they did not glorify him as God or give thanks; but became vain in their reasonings, and their senseless heart was darkened" (Rom 1:21). Hebrews warns the believing community in the same vocabulary: "Take heed, brothers, lest perhaps there will be in any one of you⁺ an evil heart of unbelief, in falling away from the living God" (Heb 3:12). Peter applies the language to the false teachers — "having a heart exercised in greed" (2 Pet 2:14) — so that across the covenants the unrenewed heart is shown as iniquity-saturated, deceit-bearing, and self-opaque.
Duplicity and Loving Evil
Inside the unregenerate diagnosis, scripture marks a particular sub-tier: the divided or double heart. The psalmist names it as the universal speech-fault — "With flattering lip, and with a double heart, they speak" (Ps 12:2) — and the prophet to the Northern Kingdom names it as the heart-fault of judgment: "Their heart is divided; now they will be found guilty" (Hos 10:2). The sage of Sirach makes it a worship-disqualification: "Do not disobey the fear of the Lord, And do not come near thereto with a double heart" (Sirach 1:28); James presses the same image on Jewish-Christian readers — "purify your⁺ hearts, you⁺ double-minded" (Jas 4:8).
Alongside duplicity, scripture registers a heart that has aligned itself with evil rather than been merely flawed. Moses warns of the man "whose heart turns away this day from [the Speech of] Yahweh our God, to go to serve the gods of those nations" (Deut 29:18). The wilderness verdict on Israel is, "It is a people who errs in their heart, And they have not known my ways" (Ps 95:10), and Hebrews quotes the verdict: "They always err in their heart" (Heb 3:10). Jeremiah curses the same disposition — "Cursed is the [noble] man who trusts in man, and makes flesh his arm, and whose heart departs from [the Speech of] Yahweh" (Jer 17:5) — and traces its outworking in Judah's covetousness: the king Jeremiah indicts has "eyes and heart ... but for your dishonest gain" (cf. Jer 22:17). The Preacher closes the loop: "the heart of the sons of man is fully set in them to do evil" (Eccl 8:11).
Hardness of Heart
A particular evil-condition of the heart, repeatedly named, is hardness. The narrative Pentateuch traces it in Pharaoh: "I will harden his heart and he will not let the people go" (Exod 4:21); "And Pharaoh's heart was hardened" (Exod 7:13); "When Pharaoh saw that there was respite, he hardened his heart" (Exod 8:15); "And Yahweh hardened the heart of Pharaoh" (Exod 9:12). The same dual-agency vocabulary is applied to Sihon — "Yahweh your God hardened his spirit, and made his heart obstinate" (Deut 2:30) — and to the Canaanite kings: "it was of Yahweh to harden their hearts, to come against Israel in battle" (Josh 11:20). The Philistine elders draw the inference for themselves: "Why then do you⁺ harden your⁺ hearts, as the Egyptians and Pharaoh hardened their hearts?" (1 Sam 6:6).
Prophets carry the diagnosis forward. Isaiah is told to "Make the heart of this people fat, and make their ears heavy, and shut their eyes" (Isa 6:10), a verdict the Fourth Gospel re-applies: "He has blinded their eyes, and he hardened their heart" (John 12:40). Ezekiel registers Israel as "impudent and stiffhearted" (Ezek 2:4) and names the inward organ as "a stiff heart" (Ezek 3:7). Wisdom warns against doing it to oneself: "he who hardens his heart will fall into mischief" (Prov 28:14). Jesus's pre-passion ministry diagnoses the disciples themselves at this register — "their heart was hardened" over the loaves (Mark 6:52) — and his Mosaic concession on divorce is grounded in the same condition: "For your⁺ hardness of heart he wrote you⁺ this commandment" (Mark 10:5). Paul fastens the same vocabulary on the unbelieving Gentile mind — "alienated from the life of God, because of the ignorance that is in them, because of the hardening of their heart" (Eph 4:18) — and presses it on his Jewish interlocutor: "after your hardness and impenitent heart [you] treasure up for yourself wrath" (Rom 2:5). Hebrews makes the same warning a present-tense imperative for the believing congregation: "Today if you⁺ will hear his voice, Do not harden your⁺ hearts" (Heb 3:8, 15).
The Renewed Heart
Against this diagnosis the prophetic and apostolic corpus fastens a second condition: the heart that Yahweh renews. The vocabulary is dense and the agency is divine. Moses promises after the curses, "Yahweh your God will circumcise your heart, and the heart of your seed, to love Yahweh your God with all your heart, and with all your soul" (Deut 30:6) — and the apostle to the Romans repeats the figure: "circumcision is that of the heart, in the spirit not in the letter" (Rom 2:29). David's penitential prayer requests the same act under a creation-verb: "Create in me a clean heart, O God; And renew a right spirit inside me" (Ps 51:10). Ezekiel narrates the substitution most explicitly: "I will give them another heart, and I will put a new spirit inside you⁺; and I will take the stony heart out of their flesh, and will give them a heart of flesh" (Ezek 11:19); "A new heart also I will give you⁺, and a new spirit I will put inside you⁺; and I will take away the stony heart out of your⁺ flesh, and I will give you⁺ a heart of flesh" (Ezek 36:26). The same prophet also issues the call from the human side: "make for yourselves a new heart and a new spirit: for why will you⁺ die, O house of Israel?" (Ezek 18:31).
Jeremiah pairs the substitution with covenant-internalization: "I will give them a heart to know me, that I am Yahweh ... for they will return to me with their whole heart" (Jer 24:7); and the new-covenant clause names the heart as the writing-tablet of Yahweh's law: "I will put my law in their inward parts, and in their heart I will write it; and I will be their God, and they will be my people" (Jer 31:33). Hebrews quotes the same clause — "I will put my laws into their mind, And on their heart also I will write them" (Heb 8:10) — and applies it to the believing congregation's drawing-near: "let us draw near with a true heart in fullness of faith, having our hearts sprinkled from an evil conscience" (Heb 10:22). Paul names the analogous illumination as a creation-act: "it is God, who said, Light will shine out of darkness, who shined in our hearts, to give the light of the knowledge of the glory of God in the face of Jesus Christ" (2 Cor 4:6). The renewed heart is exhibited not as a self-cultivated faculty but as Yahweh's gift: "Saul also went to his house to Gibeah; and there went with him the host, whose hearts God had touched" (1 Sam 10:26); "God gave him another heart" (1 Sam 10:9); "you have put such a thing as this in the king's heart, to beautify the house of Yahweh" (Ezra 7:27); "Yahweh ... had turned the heart of the king of Assyria to them" (Ezra 6:22). Solomon receives "a wise and an understanding heart" (1 Kings 3:12) and "largeness of heart, even as the sand that is on the seashore" (1 Kings 4:29) by direct grant.
The Heart's Outward Service
Where the renewed heart speaks, scripture catalogs its outworkings as a wide range of dispositions and acts. The cardinal commandment is heart-keyed obedience and love: "you will love Yahweh your God with all your heart, and with all your soul, and with all your might" (Deut 6:5); "these words, which I command you this day, will be on your heart" (Deut 6:6); "to serve Yahweh your God with all your heart and with all your soul" (Deut 10:12; cf. Deut 11:13; 26:16; 1 Kings 2:4). David and the psalmists model the obedient heart: "I have inclined my heart to perform your statutes Forever, even to the end" (Ps 119:112).
Trust, faith, and confession are heart-acts. "Trust in Yahweh with all your heart, And lean not on your own understanding" (Prov 3:5); "Though a host should encamp against me, My heart will not fear" (Ps 27:3); "His heart is fixed, trusting in [the Speech of] Yahweh" (Ps 112:7); "His heart is established, he will not be afraid" (Ps 112:8); "with the heart man believes to righteousness; and with the mouth confession is made to salvation" (Rom 10:10); "you⁺ became obedient from the heart to that form of teaching" (Rom 6:17). Heart-fear of Yahweh is its own register: "I will put my fear in their hearts, that they may not depart from me" (Jer 32:40); "my heart stands in awe of your words" (Ps 119:161). The heart's covenant-fidelity is grounded in the same divine inspection: at Abraham's call, Yahweh "found his heart faithful before [him]" (Neh 9:8). And the heart that is set to seek God is registered repeatedly: "you have put away the Asheroth out of the land, and have set your heart to seek God" (2 Chron 19:3); "that sets his heart to seek God, Yahweh, the God of his fathers" (2 Chron 30:19); "out of all the tribes of Israel, such as set their hearts to seek Yahweh ... came to Jerusalem" (2 Chron 11:16); "Ezra had set his heart to seek the law of Yahweh, and to do it, and to teach in Israel statutes and ordinances" (Ezra 7:10); "you will prepare their heart, you will cause your ear to hear" (Ps 10:17); "My heart and my flesh cry out to the living God" (Ps 84:2); "My heart said to you, My face will seek your face" (Ps 27:8); "With my whole heart I have sought you" (Ps 119:10).
The renewed heart is named as joyful: "My heart exults in Yahweh" (1 Sam 2:1); "You have put gladness in my heart, More than [they have] when their grain and their new wine are increased" (Ps 4:7); "gladness for the upright in heart" (Ps 97:11); "their heart will rejoice as through wine ... their heart will be glad in [the Speech of] Yahweh" (Zech 10:7); "my slaves will sing for joy of heart" (Isa 65:14). It is upright and devout: "those who are upright in their hearts" (Ps 125:4); "Commune with your⁺ own heart on your⁺ bed, and be still" (Ps 4:4). It is the faithful counsel-source — "discern the counsel of [your own] heart, For there is none more true to you" (Sirach 37:13); "The heart of man declares [to him] his opportunities Better than seven watchmen on a watchtower" (Sirach 37:14) — and the seat in which Christ is sanctified: "sanctify in your⁺ hearts the Lord Christ" (1 Pet 3:15). It is the wisdom-receiving organ: "he filled their heart" with "insight and understanding" (Sirach 17:5); "[he] gave them a heart to understand" (Sirach 17:7); a heart established on counsel "Will not be fearful in time [of danger]" (Sirach 22:16); "A heart fixed on thoughtful understanding Is as an ornament graven on a polished wall" (Sirach 22:17). Solomon's request crystallizes the renewed-heart's wisdom-prayer: "Give your slave therefore an understanding heart to judge your people, that I may discern between good and evil" (1 Kings 3:9).
Purity and Cleanness of Heart
A specific renewed-heart sub-register is purity. The Psalter places it as a worship-prerequisite — "He who has innocent hands, and a pure heart" may ascend Yahweh's hill (Ps 24:4); "Surely God is good to Israel, [Even] to such as are pure in heart" (Ps 73:1) — and David's penitential plea names the cleansing as a creation-act: "Create in me a clean heart, O God" (Ps 51:10). Wisdom registers the same heart-grade: "He who loves pureness of heart, [For] the grace of his lips the king will be his companion" (Prov 22:11). The apostolic letters carry the language forward. The end of the apostolic charge is "love out of a pure heart and a good conscience and faith unfeigned" (1 Tim 1:5); the call to youthful obedience is "follow after righteousness, faith, love, peace, with those who call on the Lord out of a pure heart" (2 Tim 2:22); the Petrine charge is "love one another fervently from a pure heart" (1 Pet 1:22); James joins the cleansing-call to the double-mindedness call: "purify your⁺ hearts, you⁺ double-minded" (Jas 4:8). Sincerity is the same register at a different angle — "an honest and good heart" hears the word and bears fruit (Luke 8:15); slaves serve "with fear and trembling, in singleness of your⁺ heart, as to Christ" (Eph 6:5; cf. Col 3:22).
The Broken and Tender Heart
When the heart is opened to its sin under Yahweh's hand, scripture marks a particular contrite condition. David's penitential psalm fastens it: "The sacrifices of God are a broken spirit: A broken and a contrite heart, O God, you will not despise" (Ps 51:17). The Psalter promises Yahweh's nearness to this heart: "Yahweh is near to those who are of a broken heart, And saves such as are of a contrite spirit" (Ps 34:18). The repentant return is named as a heart-act and a soul-act together — "and will return to Yahweh your God, and will obey [his Speech] according to all that I command you this day, you and your sons, with all your heart, and with all your soul" (Deut 30:2) — and Josiah is commended in the same vocabulary: "because your heart was tender, and you humbled yourself before Yahweh" (2 Kings 22:19). David's own conscience-stroke, when he had cut Saul's skirt, registers at the same tier: "David's heart struck him" (1 Sam 24:5). And outside the renewed register the same bodily heart can be melted under suffering: "My heart is like wax; It is melted inside me" (Ps 22:14); "God has made my heart faint" (Job 23:16); the prophet's heart is "disquieted" inside him at the alarm of war (Jer 4:19). Wisdom gives the same affective range: "A glad heart makes a cheerful countenance; But by sorrow of heart the spirit is broken" (Prov 15:13); "A tranquil heart is the life of the flesh; But envy is the rottenness of the bones" (Prov 14:30); a wound to the heart "severs friendship" (Sirach 22:19). The body itself is bound to the heart's condition.
The Heart Yahweh Tests
Across both registers — unrenewed and renewed — Yahweh's heart-trying is the constant. The man who serves him from a perfect heart consents to the test: "in the uprightness of my heart I have willingly offered all these things" (1 Chron 29:17). David asks for the same examination: "Examine me, O Yahweh, and prove me; Try my heart and my mind" (Ps 26:2); "Search me, O God, and know my heart: Try me, and know my thoughts" (Ps 139:23). Wisdom names the test as Yahweh's own work — "Yahweh tries the hearts" (Prov 17:3) — and Jeremiah builds it into the law of recompense: "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" (Jer 17:10). The apostles preach by the same rule — "God who proves our hearts" (1 Thess 2:4) — and the Apocalypse closes on it: "I am he who searches the minds and hearts: and I will give to each one of you⁺ according to your⁺ works" (Rev 2:23). The covenant-prayer of David fastens the same test as the ground for petition: "you try the heart, and have pleasure in uprightness" (1 Chron 29:17), and asks Yahweh to "keep this forever in the imagination of the thoughts of the heart of your people, and prepare their heart to you" (1 Chron 29:18).
If iniquity is regarded in the heart, the prayer is shut: "If I regard iniquity in my heart, The Lord will not hear" (Ps 66:18). The heart that is upright stands in awe — "my heart stands in awe of your words" (Ps 119:161) — and is the very seat in which Yahweh is sanctified. Across the testimony, the heart is exhibited as the inward organ on whose state every other thing in a man — speech, face, courage, love, prayer, obedience, judgment — turns; the organ Yahweh alone fully sees; and the organ Yahweh alone is finally able to renew.