ἀσφαλής

asphalḗs

G804 substantive adjective

SILEX Entry

Definition

Firm, secure, reliable; describes something that is stable, not liable to fall, trustworthy, or unfailing. In various contexts, it denotes physical security (not likely to fall or be overturned), reliability or certainty (cannot fail or be doubted), and sometimes safety (protected from harm).

Semantic Range

firm, secure, reliable, certain, infallible, safe, trustworthy, unfailing, not liable to fall, protected

Root / Etymology

From the negative prefix ἀ- (not) and the verb σφάλλω (to make to fall, to totter, to fail); thus, literally, 'not liable to fall'.

Historical & Contextual Notes

In pre-Koine (classical) Greek, ἀσφαλής refers primarily to physical stability or firmness—of a foundation, a wall, or a person who stands secure. Over time, particularly in Hellenistic and Koine Greek, the term broadens to describe mental or factual certainty and trustworthiness. In the Septuagint and New Testament, it frequently appears with abstract or metaphorical senses, such as the reliability of testimony (Acts 2:36), the certainty of knowledge (Luke 1:4), or secure custody (Acts 16:24). English translations often render it as 'certain,' 'sure,' 'secure,' or 'safe,' but this may not capture the dynamic sense of both physical and conceptual security conveyed in the Greek. The nuance between 'safe' (protected, not in danger) and 'certain' (not doubtful) is context-dependent. It contrasts with related terms such as ἔμπεδος (firm, fixed in place), but ἀσφαλής tends also to convey reliability or freedom from logical, moral, or physical errancy.

Translation Consistency

primary "secure" 4 occurrences

ἀσφαλής most commonly conveys the idea of being firm, safe, and reliable. “Secure” is a natural, versatile English adjective that covers physical stability, safety, and trustworthiness, and matches the majority of existing renderings—so it provides consistent, idiomatic translation across all forms.

Alternatives (1 occurrence):
"certainty" (1x)

Original Strong's Gloss (1890)

from Α (as a negative particle) and sphallo (to "fail"); secure (literally or figuratively):--certain(-ty), safe, sure.

Root Family

ἀσφαλής (asphalēs) — firm, secure, reliable, not liable to fall

Root σφαλ- to fall, to stumble

Word Forms

2 distinct forms

SIDANCE Surface Transliteration Morphology Common SIBI-P1 SIBI-P2 Occurrences
G804-02 ἀσφαλὲς asphales ADJ.S ACC N SG certainty what is secure what is secure 4
G804-01 ἀσφαλῆ asphale ADJ.S ACC F SG sure secure secure 1

Occurrences in Scripture

5 occurrences

SIDANCE Reference Word Transliteration Morphology Common SIBI-P1 SIBI-P2
G804-02 Acts 21:34 ἀσφαλὲς asphales ADJ.S ACC N SG certainty what is secure what is secure
G804-02 Acts 22:30 ἀσφαλὲς asphales ADJ.S ACC N SG certainty what is secure certainty
G804-02 Acts 25:26 ἀσφαλές asphales ADJ.S ACC N SG definite what is secure what is secure
G804-02 Philippians 3:1 ἀσφαλές asphales ADJ.P NOM N SG a safeguard what is secure secure
G804-01 Hebrews 6:19 ἀσφαλῆ asphale ADJ.S ACC F SG sure secure secure