After Rygel ascends and brings forth the light, John intones "The slug who would be king". Rudyard Kipling's 1888 story "The Man Who Would Be King" was about an English con artist who convinces people in a remote part of Afghanistan that he is a god and becomes king. After he accidentally bleeds in front of witnesses, he is recognized as mortal and is then killed by the enraged locals.
When John Crichton is asked if living a native life "was worth the trouble" he said, "Ah, what trouble?" This quote was taken from Jeremiah Johnson (1972) and was also the last line's given in the film.