Judas Iscariot
Judas Iscariot (died AD) was a disciple and one of the original Twelve Disciples of Jesus Christ. According to all four canonical gospels, Judas betrayed Jesus to the Sanhedrin in the Garden of Gethsemane by kissing him and addressing him as "Rabbi" to reveal his identity to the crowd who had come to arrest him. His name is often used synonymously with betrayal or treason. Judas's epithet "Iscariot" most likely means he came from the village of Kerioth, but this explanation is not universally accepted and many other possibilities have been suggested.
Treason
In William Shakespeare's play "King Lear" (c. 1600), when the King learns that his daughter Regan has publicly dishonoured him, he says "They could not, would not do 't; 'tis worse than murder": a conventional attitude at that time. In Dante Alighieri's "Inferno", the ninth and lowest circle of Hell is reserved for traitors; Judas Iscariot, who betrayed Jesus, suffers the worst torments of all: being constantly gnawed at by one of Lucifer's own three mouths. His treachery is considered so notorious that his name has long been synonymous with "traitor", a fate he shares with Benedict Arnold, Vidkun Quisling, Marcus Junius Brutus (who too is depicted in Dante's "Inferno", suffering the same fate as Judas along with Cassius Longinus). Indeed, the etymology of the word "traitor" originates with Judas' handing over of Jesus to the chief priests, captains of the temple and elders (Luke 22:52): the word is derived from the Latin "traditor" which means "one who delivers."
Christian theology and political thinking until after the Enlightenment considered treason and blasphemy as synonymous, as it challenged both the state and the will of God. Kings were considered chosen by God, and to betray one's country was to do the work of Satan.