Scott disagrees, and says that you don't necessarily change culture by changing religion.
"You're changing their beliefs of the heart," he said. "We're not changing how they act or certain things. It's only certain things in their heart."
When pressed, Scott conceded that some religious changes could have cultural implications, but said they believe "the principles on which America is built on is that everybody should have the freedom to choose what they believe in their own heart."
Despite numerous close calls, Scott and Decker are undaunted. The day of their interview with "Nightline," they took off for South America, with no scheduled return date.
"I'll give you a quote, and it might sound a little bit strange," Scott said. "But it was something that John Wesley said: 'I am immortal on this earth until God decides to take me.'"