Jesus, Judas, and Satan

(1) Jesus banished Satan through (Scripturally based) sole and exclusive worship of YHWH-God

(2) Jesus' ministry thwarted Satan when his followers believed in him as Messiah

(3) Satan returned when Judas worshipped 'other gods' — Military Might & Mammon

Judas worshipped Military Might
The word Iscariot means "one who is a Sicarii" (just as a Cypriot is one from Cyprus). The Sicarii were dagger (Latin Sicarius) wielding assassins, also called Zealots. They were Jewish militant Messianic extremists, who believed in a warrior Messiah who would conquer the pagan Romans. They murdered Roman collaborators and Roman government officials, as well as perpetrating other acts of terrorism.* They rejected Jesus as Messiah because of his message of peace, forgiveness, and love of both friends and foes (Matt 5:23-28). Peace, they believed, was something a warrior Messiah would impose (through violence), not engender (through non-violence).

These militant terrorist Sicarii and Zealots eventually provoked the Roman destruction of Jerusalem and its Temple in 70 CE, and the resulting decimation of the Jewish people (Josephus, Antiquities of the Jews, XVIII).

*cf. current events in Iraq.

Judas worshipped Mammon
Another reason Judas betrayed the Messiah was for money (Hebrew Mammon) — 30 silver shekels offered to him by the Head Priests (Matt 26:15):

 

Note: Simon Peter's first reaction, against the treachery of Judas the Sicarii, was — hypocritically — to resort to violence and force of arms (Matt 26:51-52; Luke 22:49-51; John 18:10-11). Simon Peter drew his sword and struck off the right ear of Malchus, the High Priest's servent. Not surprisingly, therefore, the Messiah ordered Simon Peter to stop, saying "all who take the sword will perish by the sword" (Matt 26:52). Like Judas, Simon Peter lost faith in Jesus as the Messiah, and went on to deny Jesus thrice (Matt 26:69-75; Luke 22:54-62; John 18:15-27). But, Simon Peter repented, trusted Jesus as Christ, and became one of the "pillars of the church" (Gal 2:9). Against this, Judas the Sicarii and the Zealot assassins denied Jesus as Christ, trusted instead in their blades, revolted against Rome (66-70 CE), and were annihilated — as the Messiah had prophesied.