Greek word · G805

ἀσφαλίζω

asphalizō

to secure

To make secure, fasten, or guard against escape or loss. From asphalēs, 'firm, safe, not liable to fall'. In New Testament Greek the verb usually appears in the middle form.

Appears 4 times in 4 verses of the Greek New Testament. · Updated November 01, 2026

What it means

ἀσφαλίζω

(ἀσφαλής), [in LXX: Nehemiah 3:15 (חָזַק hi.), Isaiah 41:10 (תָּמַךְ), Wisdom of Solomon 4:17 10:12 13:15 * ;]

to make firm, secure: mid., Matthew 27:65-66, Acts 16:24; pass., Matthew 27:64 (MM, see word).†

(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 Acts 16:24

Range of meaning: To make secure, fasten, or guard against escape or loss. From asphalēs, 'firm, safe, not liable to fall'. In New Testament Greek the verb usually appears in the middle form.
Against the English: KJV and YLT have 'made fast'; BSB, ESV, NIV and NASB have 'fastened'; WEB has 'secured'; NLT has 'clamped'. 'Secured' alone keeps the link to 'securely' in verse 23. 'Fastened' is accurate but hides the echo in Luke's wording.
Used elsewhere in the period: Matt 27:64–66 uses the same verb three times for the authorities who 'make secure' Jesus' tomb with a seal and guard. Acts 5:23 has a prison 'locked with all security' (asphaleia) that still fails to hold the apostles. In Greek papyri the word family is used for legal and financial 'security'.

From the study of Matthew 27:66

Range of meaning: To make firm, secure, fasten, or safeguard something against escape, loss or tampering. It is used of fastening prisoners (Acts 16:24, feet "fastened" in the stocks) and of making a place or thing safe. The related noun asphaleia means security or certainty, and the adjective asphalēs means firm or sure.
Against the English: "Made secure" (BSB, YLT, WEB) and "made sure" (KJV) are accurate. KJV's "sure" is the older English sense of "secure, safe", not "certain". "Secured the tomb" can sound like one action, but Greek grammar presents the sealing (and the guard) as the way the securing was done.
How it drifted: KJV's "made the sepulchre sure" uses "sure" in an old sense ("safe, firmly fastened") that most readers no longer use. The meaning has not otherwise shifted.
Used elsewhere in the period: Used in Greek literature and papyri for securing prisoners, goods and places (BDAG). In the New Testament: Matt 27:64, 65, 66; Acts 16:24. The Septuagint (the Greek Old Testament) uses the word group for firm safety (e.g., Wisdom 4:17, "in safety").

Similar words

Where it appears

Matthew · 3

Matthew 27:64 ἀσφαλισθῆναι to be secured

So give the order that the tomb be secured until the third day. Otherwise, His disciples may come and steal Him away and tell the people He has risen from the dead. And this last deception would be worse than the first.”
Matthew 27:65 ἀσφαλίσασθε do make [it as] secure

“You have a guard,” Pilate said. “Go, make the tomb as secure as you know how.”
Matthew 27:66 ἠσφαλίσαντο they made secure

So they went and secured the tomb by sealing the stone and posting the guard.

Here: The main verb: "they made it fast". It is the third time in three verses (27:64, 65, 66) that Matthew uses this word. The form is middle voice, roughly "they had it secured for their own purposes": the leaders are protecting their own interest.

Acts · 1

Acts 16:24 ἠσφαλίσατο fastened

On receiving this order, he placed them in the inner cell and fastened their feet in the stocks.

Here: 'He secured.' It comes from the same root as 'securely' (asphalōs) in verse 23, so the jailer carries out the word 'securely' to the letter. Luke is setting up the irony of the earthquake that follows.

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