Strong’s Greek
G3143 — marturomai
The entry below is Strong’s own definition (1890, public domain), and every verse where the word occurs.
μαρτύρομαι
marturomai — pronounced mar-too'-rom-ahee
middle voice from 3144; to be adduced as a witness, i.e. (figuratively) to obtest (in affirmation or exhortation):--take to record, testify. see GREEK for 3144
2 occurrences in the KJV.
Galatians 5:3
For I testify again to every man that is circumcised, that he is a debtor to do the whole law.
Ephesians 4:17
This I say therefore, and testify in the Lord, that ye henceforth walk not as other Gentiles walk, in the vanity of their mind,