μαρτυρέωmartyréō

(a) properly, to be a witness, bear witness, testify: absolutely (Pind., and elsewhere), John 15:27, Acts 26:5; parenthetical, 2 Corinthians 8:3; with dative of person (comm. et incomm.; Bl., § 37, 2), Acts 22:5, Hebrews 10:15; id. followed by ὅτι, Matthew 23:31, Romans 10:2, and elsewhere; accusative et infinitive, Acts 10:43; with accusative of thing (classical Greek), John 3:11, Revelation 22:16, Revelation 22:20; with accusative cognate, followed by περί, John 5:32, 1 John 5:10; with dative of thing, John 5:33, Acts 14:3, and elsewhere; followed by περί, with genitive (person et rei), John 1:7, John 1:8, John 1:15, John 2:25, John 18:23, John 21:24, and elsewhere; id. followed by ὅτι, John 5:36, John 7:7; ὅτι, John 1:34, John 4:44 and elsewhere; ὅτι recit., John 4:39; κατά followed by ὅτι, 1 Corinthians 15:15; passive, Hebrews 7:8; participle, Romans 3:21; impers., Hebrews 7:17

(b) in late Gk., to witness favourably, give a good report, approve: with dative of person, Luke 4:22; followed by ἐπί with dative of thing, Hebrews 11:4; passive, Acts 6:3; followed by ἐν, 1 Timothy 5:10, Hebrews 11:2; διά, with genitive of thing, Hebrews 11:39; with genitive of person, Acts 10:22, and elsewhere; impers., 3 John 1:12 (cf. ἐπι-, συν-επι-, κατα-, συν-μαρτυρέω).