βεβαι-όω,
confirm, establish, make good, τοῖς δικασταῖς τὴν δόξαν [[ 5th-6th c.BC: Plato Philosophus “Crito” 53b; δωρεὰν 4th c.BC: Isaeus Orator 1.18; εἴτε δεξιὰς δοῖεν ἐβεβαίουν 5th-6th c.BC: Xenophon Historicus “Institutio Cyri (Cyropaedia)” 8.8.2, etc.] Refs 5th c.BC+]; ἔργῳ βεβαιούμενα, opposed to ἀκοῇ λεγόμενα, [[ 5th c.BC: Thucydides Historicus 1.23 ] Refs 5th c.BC+]; β. λόγον make good one's word, [[ 5th c.BC: Lysias Orator 20.32; β. τὴν πρᾶξιν 5th-6th c.BC: Xenophon Historicus “Anabasis” 7.6.17 ] Refs 5th c.BC+]; treat as valid, τὰς αὑτῶν αἰσθήσεις [[ 4th c.AD: Metrodorus Epigrammaticus 1, compare 4th-3rd c.BC: Epicurus Philosophus “Sententiae” 24 ] Refs 4th c.BC+]; β. τινί τι secure one the possession of a thing, οὐδ᾽ ἡμῖν αὐτοῖς βεβαιοῦμεν [τὴν ἐλευθερίαν] [[ 5th c.BC: Thucydides Historicus 1.122; τοῖς θεοῖς βεβαιοῦντες τοὺς νόμους οὒς ἐψηφίσασθε 5th c.BC: Lysias Orator 6.29, compare 4th c.BC: Demosthenes Orator 21.30; τὴν ἀρχήν τινι 1st-2nd c.AD: Plutarchus Biographus et Philosophus “Sulla” 22; τὸν λόγον NT.Mark.16.20 ] NT+5th c.BC+]:—middle, establish for oneself, secure, σφᾶς αὐτούς [[ 5th c.BC: Thucydides Historicus 1.33 ] Refs 5th c.BC+]; τὴν ἀρχήν, τὴν φιλίαν τινός, [[ [prev. author] 6.10, 78 ] Refs]; β. τινάς confirm them in one's interest,[[ [prev. work] 34; βασιλείαν 2nd c.AD: Pausanias Periegeta 3.11.4; τὰ περὶ τῆς βοηθείας 2nd c.BC: Polybius Historicus 2.51.5. ] Refs 2nd c.BC+]
__2 middle, secure one's ground in argument, [[ 5th-6th c.BC: Plato Philosophus “Theaetetus” 169e ] Refs 5th c.BC+]; confirm oneself in an opinion, [[ [prev. author] “Grg.” 489a, “Prt.” 348d. ] Refs]
__3 guarantee the validity of a purchase, warrant the purchaser's title, β. τινὶ τὸ βαλανεῖον [[ 4th c.BC: Isaeus Orator 5.23, compare 4th-3rd c.BC: Dinarchus Orator 1.42, 4th c.BC: Demosthenes Orator 37.12, “SIG” 46.4 (Halic., 5th c.BC)] Refs 5th c.BC+]; τὴν μίσθωσιν [[ “BGU” 1119.47 (1st c.BC)] Refs 1st c.BC+]: generally, β. τοὺς κανόνας [[ 2nd c.AD: Arrianus Historicus “Epicteti Dissertationes” 2.11.24. ] Refs 2nd c.AD+]