μαρτύρομαιmartýromai

to summon as witness, hence

Greek (New Testament) · G3143

Meanings

(a) to protest, affirm solemnly: followed by ὅτι, Acts 20:26, Galatians 5:3

(b) to adjure, beseech: with dative of person, Acts 26:22; with accusative et infinitive, Ephesians 4:17; followed by εἰς, 1 Thessalonians 2:12 (cf. δια-, προ-μαρτύρομαι).

Same root

Where it appears

Appears 4 times in the Bible.

  • Acts 20:26 I declare today that I have been faithful. If anyone suffers eternal death, it’s not my fault,
  • Acts 26:22 But God has protected me right up to this present time so I can testify to everyone, from the least to the greatest. I teach nothing except what the prophets and Moses said would happen—
  • Galatians 5:3 I’ll say it again. If you are trying to find favor with God by being circumcised, you must obey every regulation in the whole law of Moses.
  • Ephesians 4:17 With the Lord’s authority I say this: Live no longer as the Gentiles do, for they are hopelessly confused.

Source: G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922), public domain.