The story
The term comes from the Gospel of Luke chapter 22, verse 48 of the New Testament: ⁴⁷ While He was still speaking, a crowd arrived, led by the man called Judas, one of the Twelve. He approached Jesus to kiss Him. ⁴⁸ But Jesus asked him, “Judas, are you betraying the Son of Man with a kiss?” The Gospel of Luke, Berean Standard Bible.
Etymology from Wiktionary, CC BY-SA 4.0.