Augustine of Hippo

"I spoke of Your testimonies also," he says, "before kings, and I was not ashamed" [Psalm 119:46]: as one who had sought and had received grace to answer those who reproached him with the word, and the promise that the word of truth should not be taken from his mouth. Struggling for this truth even unto death, not even before kings was he ashamed to speak of it. For testimonies, whereof he does avow that he was speaking, are in Greek styled μαρτύρια, a word which we now employ instead of the Latin. The name of "Martyrs," unto whom Jesus foretold, that they should confess Him even before kings, [Matthew 10:18] is derived hence.