"An Eternal Battle…!!" (永遠なる闘い…!!, Eiennaru Tatakai…!!) is chapter 124 of the original Naruto manga.
Despite Enma's efforts, Sarutobi is stabbed in the back by Orochimaru's Kusanagi. Orochimaru assures him that he will now die, but Sarutobi is unconcerned, his death guaranteed because of the Dead Demon Consuming Seal. Sarutobi explains the nature of the seal, how it defeated the Nine-Tailed Demon Fox, and then struggles to find the strength to complete the sealing of Orochimaru's soul. Meanwhile, Jiraiya finally takes part in Konoha's defence, stopping the snakes rampaging through the village. Elsewhere, Sasuke catches up to the Three Sand Siblings. Kankurō volunteers to fight Sasuke to give Gaara a chance to escape, but Shino appears and volunteers to fight Kankurō to give Sasuke a chance to catch up to Gaara again.