The very first live performance of "The Judas Kiss" was on February 25th 2009 at the Trent FM Arena, Nottingham, UK. This was the first show of the European leg of the World Magnetic tour and was the first time the band had ever played live in Nottingham city.
"The Judas Kiss" refers to the biblical account of Judas Iscariot, an apostle who marked Jesus to the chief priests for a bribe by kissing him on the cheek. This is converted into a metaphor for the darkness in all of man through betrayal. It is particularly stinging toward all religious indoctrination in general, as evidenced by the line "helps the kings abuse their crown" and "in the heart of evil man, plant the seeds of my own plan, strong and powerful will fall, find a piece of me in all".
Another point of speculation is a possible reference to the attack on September 11th, which was driven by religious dogma. This can be found in the line, "watched your towers hit the ground".