Strong’s G4645: A verb meaning “to harden” or “make hard,” used particularly in spiritual contexts to describe the hardening of hearts against divine truth. Appears both in active sense of willful resistance and passive sense of judicial hardening, especially in references to Pharaoh’s heart.

U- Unveiling the Word

Σκληρύνω represents a critical spiritual concept in Scripture, describing both the process and result of spiritual resistance to God’s truth. The word carries special significance in discussions of human responsibility and divine sovereignty, particularly in Paul’s treatment of Pharaoh’s hardening (Romans 9:18). Early church fathers extensively debated its implications for free will and predestination. Today, it continues to prompt reflection on the interplay between human choice and divine action in spiritual responsiveness.

Save 20% with code – FOG20

N – Necessary Information

• Greek Word: σκληρύνω, sklērynō, sklay-ROO-no
• Detailed Pronunciation: σκλη (sklay) ρύ (ROO) νω (no) – stress on second syllable
• Part of Speech: Verb

Etymology:

• From σκληρός (hard, tough)
• -ύνω verbal suffix indicating causative action
• Related to process of becoming or making hard

D – Defining Meanings

• To make hard
• To harden oneself
• To become stubborn
• To resist divine truth

Translation Options:

• To harden – emphasizing the process
• To make stubborn – focusing on the result
• To become resistant – highlighting the progression

E – Exploring Similar Words

• πωρόω (pōroō, po-RO-o) – See G4456: To petrify, make callous
• σκληρύνομαι (sklērynomai, sklay-ROO-no-mai) – Passive form
• ἀπειθέω (apeitheō, a-pay-THE-o) – See G544: To be disobedient

R – Reviewing the Word’s Morphology

• Tense: Present, Aorist
• Voice: Active, Passive
• Mood: Indicative, Subjunctive, Imperative
• Person and Number: All forms possible

The verb can appear in both active (“to harden”) and passive (“to be hardened”) voices, with the passive often carrying theological significance in divine action contexts.

S – Studying Lexicon Insights

BDAG emphasizes its theological usage. Thayer’s notes its connection to Exodus narratives. LSJ documents literal and metaphorical uses. Vine’s highlights its importance in Romans. Moulton and Milligan cite examples from religious contexts.

T – Tracing the Scriptures

First appearance:
Acts 19:9: “But some of them became obstinate; they refused to believe and [hardened] [σκληρύνω] themselves and publicly maligned the Way.”

Additional References:
Romans 9:18, Hebrews 3:8, Hebrews 3:13, Hebrews 3:15

A – Analyzing Classical Usage

N – Noteworthy Summary

Σκληρύνω warns us about the danger of resisting God’s truth while revealing His sovereignty in all spiritual matters. The good news is that King Jesus can soften the hardest heart and calls us to respond to His grace while there is still time.

D – Did You Know?

• Used extensively in the Exodus narrative in the Septuagint
• Appears in both active human choice and passive divine action contexts
• Central to theological discussions about free will and sovereignty

Strong’s G4645: A verb meaning “to harden” or “make hard,” used particularly in spiritual contexts to describe the hardening of hearts against divine truth. Appears both in active sense of willful resistance and passive sense of judicial hardening, especially in references to Pharaoh’s heart.

Part of speech: Verb

Tags: hardening, resistance, pharaoh, divine-sovereignty, human-responsibility, free-will, stubbornness, heart-condition, warning, hebrews, romans, spiritual-resistance​​​​​​​​​​​​​​​​