Greek word · G4645

σκληρύνω

sklērynō

to harden

To make hard, stiff or dry. Used figuratively for making the heart or neck stubborn and unresponsive. In the Greek Old Testament it is the standard verb for Pharaoh's hardened heart (Exodus 4:21; 7:3) and for Israel's stiff neck (Deuteronomy 10:16; 2 Kings 17:14).

Appears 6 times in 6 verses of the Greek New Testament. ·

What it means

σκληρύνω

(σκληρός), [in LXX chiefly for קָשָׁה hi., also for חָזַק ;]

to harden. Metaphorical, to harden, make stubborn: with accusative of person(s), Romans 9:18; T. καρδίας (Psalms 95:8), Hebrews 3:8, 15 4:7. Pass., to become hardened: Acts 19:9, Hebrews 3:13.†

(AS)

From G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922), via STEPBible.org (CC BY 4.0).

In depth

From the study of Hebrews 3:13

Range of meaning

To make hard, stiff or dry. Used figuratively for making the heart or neck stubborn and unresponsive. In the Greek Old Testament it is the standard verb for Pharaoh's hardened heart (Exodus 4:21; 7:3) and for Israel's stiff neck (Deuteronomy 10:16; 2 Kings 17:14).

Against the English

All the major versions have 'hardened,' which is accurate. NLT has 'deceived by sin and hardened against God,' which spells out the direction of the hardening.

How it drifted

In English a 'hard-hearted' person is usually emotionally cold or unkind. In the Bible the heart is the seat of thinking, deciding and choosing, so a hardened heart is a stubborn will that no longer responds to God's word. It is a spiritual deafness more than a lack of feeling.

Used elsewhere in the period

Psalm 95:8 in the Greek Old Testament: 'Do not harden (sklērynēte) your hearts as at the Rebellion.' That refers to Massah and Meribah (Exodus 17) and to the refusal at Kadesh (Numbers 14). The same verb is used in Acts 19:9 and Romans 9:18.

From the study of Hebrews 3:15

Range of meaning

To make hard, stiff or rigid. Used figuratively of making oneself or someone else stubborn and unresponsive.

Against the English

"Harden" is the right word. The image is less about emotional coldness, as in modern "hard-hearted," and more about stiffness: a will that will not bend.

Used elsewhere in the period

In the LXX it renders Hebrew qashah (to be or make hard) and chazaq (to make strong or firm). It is used of Pharaoh's heart (Exod 7:3; 13:15) and of Israel's stiff neck (Deut 10:16; 2 Kgs 17:14, "they hardened their necks… who did not believe in the LORD"). Also Acts 19:9 and Rom 9:18. Hebrews 3:13 uses the passive: "lest any of you be hardened by the deceitfulness of sin."

From the study of Hebrews 3:8

Range of meaning

To make hard, stiff or rigid. Used figuratively for being obstinate and unyielding. Related words in the same family mean "stiff-necked" (σκληροτράχηλος) and "hardness of heart" (σκληροκαρδία).

Against the English

"Harden" is accurate. Modern English tends to hear "hard-hearted" as unkind or uncaring toward people. The biblical picture is different: a mind and will set against God's voice, stubborn and unwilling to bend.

How it drifted

In English idiom, "hard-hearted" became mainly a word for lack of compassion. The biblical idiom is about refusing to listen and obey.

Used elsewhere in the period

In the Greek Old Testament (the Septuagint) it is used repeatedly for Pharaoh's heart (Exod 4:21; 7:3; 14:4). It translates Hebrew qashah, "be hard/stiff" (the verb in Ps 95:8), and chazaq, "be strong/firm". Compare "stiffen the neck" (Deut 10:16; 2 Kgs 17:14; Jer 7:26). In the NT: Acts 19:9 (people "hardened" and would not believe); Rom 9:18; Heb 3:13, 15; 4:7.

Where it appears

Acts · 1

  1. Acts 19:9 ἐσκληρύνοντο were hardened

    But when some of them stubbornly refused to believe and publicly maligned the Way, Paul took his disciples and left the synagogue to conduct daily discussions in the lecture hall of Tyrannus.

    Here: "They were becoming hard." The imperfect tense shows a growing stiffness. The form can be read as "they hardened themselves" or "they were being hardened." It is the vocabulary of Pharaoh and of Israel in the wilderness ('do not harden your hearts').

Romans · 1

  1. Romans 9:18 σκληρύνει.¶ He hardens.

    Therefore God has mercy on whom He wants to have mercy, and He hardens whom He wants to harden.

    Here: To make someone hard, meaning stubborn and unresponsive to God's word and warnings. It points straight back to the Greek Exodus wording about Pharaoh's heart. Again the present tense describes how God acts.

Hebrews · 4

  1. Hebrews 3:8 σκληρύνητε shall harden

    do not harden your hearts, as you did in the rebellion, in the day of testing in the wilderness,

    Here: Aorist subjunctive with μή: the normal Greek way to forbid an action outright, "don't do this." It is active and second person. The hearers would be doing the hardening themselves. It is a stubborn refusal they choose, not something that happens to them.

  2. Hebrews 3:13 σκληρυνθῇ may be hardened

    But exhort one another daily, as long as it is called today, so that none of you may be hardened by sin’s deceitfulness.

    Here: Aorist passive subjunctive: 'become hardened.' It echoes Psalm 95:8 in the Greek Old Testament, 'do not harden your hearts.' The psalm puts it as something you do; here it is something done to you, by sin's trickery. The picture is a heart that has grown stiff and unresponsive to God's voice.

  3. Hebrews 3:15 σκληρύνητε shall harden

    As it has been said: “Today, if you hear His voice, do not harden your hearts, as you did in the rebellion.”

    Here: "Make hard, stiff, unyielding." The hearers are told not to do this to themselves. It recalls Pharaoh in Exodus and Israel as "stiff-necked": a stubborn refusal to give way to what God says.

  4. Hebrews 4:7 σκληρύνητε shall harden

    God again designated a certain day as “Today,” when a long time later He spoke through David as was just stated: “Today, if you hear His voice, do not harden your hearts.”

    Here: 'Do not make hard.' The aorist form here works as 'don't start doing this,' a warning against a decisive act of stubbornness. The word recalls Pharaoh's hardened heart.

Word data: STEPBible.org (CC BY 4.0), main text only.