3975. pachunó

Lexical Summary

pachunó: To make thick, to fatten, to dull

Original Word: παχύνω
Part of Speech: Verb
Transliteration: pachunó
Pronunciation: pä-khoo'-no
Phonetic Spelling: (pakh-oo'-no)
KJV: wax gross
NASB: become dull
Word Origin: [from a derivative of G4078 (πήγνυμι - pitched) (meaning thick)]

1. to thicken
2. (by implication) to fatten
3. (figuratively) stupefy or render callous

Strong's Exhaustive Concordance

become dull

From a derivative of pegnumi (meaning thick); to thicken, i.e. (by implication) to fatten (figuratively, stupefy or render callous) -- wax gross.

see GREEK pegnumi

HELPS Word-studies

3975 paxýnō (from paxys, "thick") – properly, thick (with excessive fat); (figuratively) having an insensitive heart, i.e. unfeeling (obtuse).

NAS Exhaustive Concordance

Word Origin
from pachus (thick)
Definition
to thicken, to fatten, fig. to make dull
NASB Translation
become dull (2).

Thayer's Greek Lexicon

STRONGS NT 3975: παχύνω

παχύνω: 1 aorist passive ἐπαχυνθην; (from παχύς (thick, stout); cf. βραδύνω; ταχύνω); to make thick; to make fat, fatten: τά σώματα, Plato, Gorgias, p. 518 c.; βοῦν, de rep., p. 343 b.; ἵππον, Xenophon, oec. 12, 20. Metaphorically, to make stupid (to render the soul dull or callous): τάς ψυχάς, Plutarch, mor., p. 995 d. (i. e. de esu carn. 1, 6, 3); νοῦν, Philostr. vit. Apoll. 1, 8; παχεῖς τάς διανοίας, Herodian, 2, 9, 15 (11 edition, Bekker); τήν διάνοιαν, Aelian v. h. 13, 15 (Latinpingue ingenium) (cf. Winer's Grammar, 18); ἐπαχύνθη ἡ καρδία (Vulg.incrassatum (A. V. their heart is waxed gross)): Matthew 13:15; Acts 28:27, after Isaiah 6:10 (for לֵב הַשְׁמֵן).

Topical Lexicon

Root Idea and Biblical Imagery

The verb pictures something so coated with fat or thickness that its normal sensitivity is lost. Scripture applies the term to the human heart, portraying a progressive callousness toward God’s self-revelation. The image contrasts sharply with the biblical ideal of a heart of flesh that trembles at His word (Isaiah 66:2).

New Testament Usage

1. Matthew 13:15 – Jesus quotes Isaiah after the Parable of the Sower: “For this people’s heart has grown dull (ἐπαχύνθη), their ears can barely hear, and they have closed their eyes.” The thickened heart explains why the same seed (the word of the kingdom) that bears fruit in some is resisted by others.
2. Acts 28:27 – Paul cites the same prophecy to Jews in Rome who reject his witness: “For this people’s heart has grown dull (ἐπαχύνθη)… otherwise they might see with their eyes, hear with their ears, understand with their hearts and turn, and I would heal them.” The Spirit-inspired history book of Acts closes by highlighting the peril of spiritual insensibility and the widening mission to the Gentiles.

Old Testament Background

Isaiah 6:9–10 is the fountainhead. Israel’s persistent unbelief would result in judicial hardening; yet Isaiah’s very commission anticipated a purified remnant (Isaiah 6:13). The Septuagint uses the same verb family for fattened hearts (Psalm 119:70), thick lips (Psalm 17:10), and necks weighed down with fat (Jeremiah 5:28). Each context links overindulgence or complacency with moral dullness.

Theological Significance

1. Human Responsibility and Divine Judgment – Repeated refusal of revelation culminates in God’s act of hardening, yet never absolves personal accountability (Romans 2:5).
2. Revelation and Illumination – The dull heart is not an intellectual problem but a moral one; only the Spirit can strip away the fat that muffles conscience (2 Corinthians 3:14–16).
3. Remnant Hope – Even where hearts have grown thick, the promise remains: “They might… turn, and I would heal them.” Grace pursues the hardened, offering restoration through repentance and faith.

Ministry Applications

• Preaching and Teaching – Faithful proclamation must expose the danger of a thickened heart while extending the healing word of Christ. Both Jesus and Paul model expository engagement with Isaiah to diagnose spiritual deafness.
• Evangelism – Workers should expect resistance identical to that encountered by the prophets, the Messiah, and the apostles, yet remain confident that some hearers will be granted ears to hear (Acts 13:48).
• Self-Examination – Churches and individuals must guard against incremental callousness—neglect of Scripture, habitual sin, and worldly excess can coat the heart even of covenant people (Hebrews 3:12-13). Regular confession and obedience keep sensitivity alive.

Pastoral Warnings and Promises

“Today, if you hear His voice, do not harden your hearts” (Hebrews 4:7). The same voice that once pronounced judgment now invites renewal: “I will give you a new heart and put a new spirit within you” (Ezekiel 36:26). The thickened heart can be cut open by the “living and active” word of God (Hebrews 4:12), producing the fruitfulness pictured in the good soil.

Eschatological Perspective

Matthew 13 situates the dull heart within the mystery of the kingdom: a present age marked by mixed responses until the harvest. Acts 28 points forward to the full ingathering of the nations while holding out mercy to ethnic Israel (Romans 11:25-27). Hearts once fattened can yet be grafted in again—proof that divine hardening is never the final word for those who turn to the Lord.

Forms and Transliterations

επάχυνεν επαχυνθη επαχύνθη ἐπαχύνθη επαχύνθησαν επεδήθησαν παχείς παχέος παχύ παχυνθή παχυτέρα παχύτετος πεδήσαντας πεπεδημένοι πεπεδημένους πεπεδημένων epachunthe epachunthē epachynthe epachynthē epachýnthe epachýnthē

Englishman's Concordance

Matthew 13:15 V-AIP-3S
GRK: ἐπαχύνθη γὰρ ἡ
NAS: PEOPLE HAS BECOME DULL, WITH THEIR EARS
KJV: heart is waxed gross, and
INT: has grown dull indeed the

Acts 28:27 V-AIP-3S
GRK: ἐπαχύνθη γὰρ ἡ
NAS: PEOPLE HAS BECOME DULL, AND WITH THEIR EARS
KJV: people is waxed gross, and
INT: has grown dull indeed the

Strong's Greek 3975
2 Occurrences

ἐπαχύνθη — 2 Occ.