One who betrays another’s trust, is false to a duty, or acts treasonously against his country or ruler. The most infamous traitor of the Bible was “Judas Iscariot, who turned traitor.” (Lu 6:16) The Greek noun pro·doʹtes (“betrayer; traitor,” from a verb meaning “give forth or over; betray”) aptly describes Judas, for after being selected as an apostle, he became a greedy, practicing thief (Joh 12:6) and finally betrayed Jesus to the authorities for a comparatively small sum. (Mt 26:14-16, 25, 48, 49) His was not merely a temporary abandoning of Christ by fleeing from what appeared to be a dangerous situation (Mr 14:50) but was a deliberate betrayal of Jesus to those seeking his death.

 The Jewish religious leaders were correctly termed “betrayers and murderers,” for they employed traitorous Judas, personally turned their fellow countryman Christ over to the Romans, and then, in an outrage of justice, opposed the declaration of Jesus’ innocence and demanded his death.​—Joh 18:28–19:16; Ac 3:13-15; 7:52.

Another outstanding example of a traitor listed in the Bible was Ahithophel. Though having been King David’s trusted counselor, he joined Absalom’s insurrection. (2Sa 15:12, 31; 16:20-23; compare Ps 55:20, 21.) God thwarted the traitorous adviser’s counsel, leading to Ahithophel’s death by suicide. (2Sa 17:23) Evidently David had other experiences with persons who turned against him. A number of modern Bible translations render the plural Hebrew participial form of ba·ghadhʹ (meaning “deal treacherously”) as “traitors” at Psalm 59:5: “Do not show favor to any hurtful traitors.” (JB, NE, NW, Mo) The superscription of the psalm suggests that it relates to the time when Saul sent men to watch David’s house in order to kill him. (1Sa 19:11-18) So the “traitors” mentioned at Psalm 59:5 may have been associates of David who had deserted him or who were willing to betray him in that hour of trial. Or, since the preceding words call on God to turn his attention to “all the nations,” the term “traitors” may have referred to all opposers of God’s will, whether inside or outside Israel.

The prophecy in 2 Timothy 3:1-5 about conditions to exist in “the last days” indicates that there would be many betrayers, or traitors (Gr., pro·doʹtai). Christians were advised to “turn away” from such, as befits persons striving to be loyal and honest in all things.​—1Th 2:10; Heb 13:18.