G0949
βέβαιος
firm
βέβαιος, -ον (also -α, -ον; βαίνω), [in LXX: Est.3:13, Wis.7:23, 3Ma.5:31 7:7, 4Ma.17:4 * ;] firm, secure: ἄγκυρα, Heb.6:19; metaphorically, sure (esp. "in the sense of legally guaranteed security," Deiss., BS, 109; cf . two foll. words): ἐπαγγελία, Rom.4:16; ἐλπίς, 2Co.1:6; λόγος, Heb.2:2; παρρησία, Heb.3:6; ἀρχή (τ. ὑποστάσεως), Heb.3:14; διαθήκη, Heb.9:17; κλῆσις κ. ἐκλογή, 2Pe.1:10; comp. (-ότερος), προφητικὸς λόγος, 2Pe.1:19.† (AS)
Full Thayer's lexicon entry
βέβαιος — bébaios
βέβαιος, βεβαία (Winers Grammar, 69 (67); Buttmann, 25 (22)), βέβαιον (ΒΑΩ, βαίνω) (from Aeschylus down), stable, fast, firm; properly: ἄγκυρα, Heb 6:19; metaphorically, sure, trusty: ἐπαγγελία, Rom 4:16; κλῆσις καί ἐκλογή, 2Pe 1:10; λόγος προφητικός, 2Pe 1:19; unshaken, constant, Heb 3:14; ἐλπίς, 2Co 1:7 (6) (4Ma 17:4); παρρησία, Heb 3:6 (but WH Tr marginal reading in brackets); valid and therefore inviolable, λόγος, Heb 2:2; διαθήκη, Heb 9:17. (With the same meanings in Greek writings from Herodotus down.)
8 occurrences
Romans (1), Hebrews (5), II Peter (2)