ἀσφαλής

ἀσφαλής — asphalḗs

ἀσφαλής, ἀσφαλές (σφάλλω to make to totter or fall, to cheat (cf. Latinfallo, German fallen, etc., English fall, fail), σφάλλομαι to fall, to reel) (from Homer down);

a. firm (that can be relied on, confided in): ἄγκυρα, Heb 6:19 (where I, and Tr have received as the form of accusative singular ἀσφαλην (Tdf.7ἀσφαλην; cf. Tdf. at the passage; Delitzsch, commentary at the passage) see ἄρσην). Tropically, certain, true: Act 25:26; τό ἀσφαλές, Act 21:34; Act 22:30.

b. suited to confirm: τίνι, Php 3:1 (so Josephus, Antiquities 3, 2, 1).