"to harden; met. to harden morally, to make stubborn, Heb. 3:8, 15; 4:7; as a negation of ἐλεεῖν, to leave to stubbornness and contumacy, Rom. 9:18; mid. and pass. to put on a stubborn frame, Acts 19:9; Heb. 3:13*"
Definition and meaning
to harden; met. to harden morally, to make stubborn, Heb. 3:8, 15; 4:7; as a negation of ἐλεεῖν, to leave to stubbornness and contumacy, Rom. 9:18; mid. and pass. to put on a stubborn frame, Acts 19:9; Heb. 3:13*
In the original Greek the word is written: σκληρύνω
Historical context
The Roman Empire provided infrastructure no previous civilization had built — roads, sea routes, a common language in Greek, and relative peace across the Mediterranean. Jewish synagogues existed in every major city, giving Paul a starting point everywhere he traveled. The early church had no buildings, no political power, no social standing — and spread faster than any movement in ancient history.
The people who first heard this word were not reading a book — they were living through empires, oppression, exile, and covenant. Every word carried the weight of that reality. Understanding it changes how you read Scripture.
Scripture references
These are the most notable occurrences of skleryno (G4645) across the King James Bible.
But when divers were hardened, and believed not, but spake evil of that way before the multitude, he departed from them, and separated the disciples, disputing daily in the school of one Tyrannus.
Therefore hath he mercy on whom he will have mercy, and whom he will he hardeneth.
Harden not your hearts, as in the provocation, in the day of temptation in the wilderness:
But exhort one another daily, while it is called To day; lest any of you be hardened through the deceitfulness of sin.
While it is said, To day if ye will hear his voice, harden not your hearts, as in the provocation.
Again, he limiteth a certain day, saying in David, To day, after so long a time; as it is said, To day if ye will hear his voice, harden not your hearts.
Refiner gives you the full lexicon entry, AI-powered verse insight, historical commentary, cross-references, and voice study — all in one place.
Free to start · Disciple $4.99/mo · Shepherd $9.99/mo
Common questions
Strong's G4645 (skleryno) is a Greek word that means: to harden; met. to harden morally, to make stubborn, Heb. 3:8, 15; 4:7; as a negation of ἐλεεῖν, to leave to stubbornness and contumacy, Rom. 9:18; mid. and pass. to put on a stubborn frame, Acts 19:9... It appears 6 times in the King James Bible.
The word skleryno (G4645) appears 6 times in the original Greek text.
Strong's G4645 is skleryno, a Greek word defined as: to harden; met. to harden morally, to make stubborn, Heb. 3:8, 15; 4:7; as a negation of ἐλεεῖν, to leave to stubbornness and contumacy, Rom. 9:18; mi. James Strong catalogued this in his 1890 concordance to help English readers study the original languages of the Bible.
skleryno is a Greek word found in the New Testament.