Christian missionaries Timothy Scott and Will Decker face danger in their quest to spread their message around the world, but they'd never faced anything as treacherous as a blizzard they encountered in the middle of the Mongolian desert.
Scott and Decker, both in their 30s, are what you might call gonzo missionaries. Armed with a video camera, a backpack and the faith that Jesus is the only way to heaven, they travel around the world in the hopes of converting "the unreached." That's what they call native populations who have not heard the gospel.
At the same time, they produce a show called "Travel the Road," which airs on the Trinity Broadcasting Network.
"In this you can't survive more than two hours," Scott said on the show, describing the bitter cold and blizzard conditions. "We're going to walk and pray that the Lord will lead us out of this whiteout."
"It's insane how cold it is here," Decker said. "It's like the edge of the moon."
The two admit they have a crazy lifestyle. They've been stalked by lions in Ethiopia and menaced by leeches in Borneo. They've braved gunfire in Burundi, navigated streets filled with gun-toting militias in Somalia and fallen out of moving trucks in Sudan. They've eaten wild monkey, and tried to eat a pungent tropical fruit called "durian."
"It's great, we love it," Decker said. "There is nothing better than when you're getting on the plane. You got your ticket and you got everything that you own in one backpack, and you got a couple pair of clothes. You got your Bible and you got your camera gear. And it's open."
They're willing to take these risks and travel to areas of conflict and war "because we've really been called from the beginning," Decker said.
"Our whole desire is to preach the gospel and the places we usually end up are areas that have never heard the gospel or never had any contact or don't know of the name of Jesus … places that have been cut off from any gospel work being done," he said.
"From what we know in our heart and what we know of the message that we carry, how can we not do it?" Scott said.
They say it's important for them to "share the word of God," because as evangelical Christians they believe that those who don't accept the Gospel will go to hell.
As a young man, Scott planned to be a stockbroker until, he said, God told him to become a missionary. Decker wasn't even a believer when the pair went on their first trip in 1998, but that changed as they traveled through Papua New Guinea.
"I just gave my life to the Lord and just said, 'Lord, come live in me, forgive me of my sins, and I believe you went to the cross and died for me and your blood was shed for me. Just forgive me of my sins,'" he said. "I felt a total release when I prayed that and that was the beginning for us."
During the snowstorm in Mongolia, the two did find a tent and a family who offered them hot soup.
"Once again, the Lord has provided and we're not going to die out here, which is good," Scott said.
He said that it was a reminder of what brought them there: "the people" and "the message."
But their troubles didn't end there -- the next day their drivers decided not to let them go, in what the missionaries described as a kidnapping. Decker called it "one of the strangest and scariest trips I've started on."
After 24 hours, they were aided by a police officer at a truck stop and escaped unharmed.
"In that situation we're not completely absolved of fear," Decker said. "We're like, 'Oh Lord, protect us, keep us right now.' And in that situation God did, but when you go through those there are always moments you can look back on and say, you know, 'If God got us through that we can get through the next thing.'"
Dangerous encounters lead them to have more faith, Scott said, but not to take "unnecessary risk."
"We're wise as a serpent, gentle as a dove," he said. "So when we get out there, you learn certain things like being streetwise. How to move inside certain countries and you take faith in doing it."
Recently, one of their adventures created controversy. They embedded with the U.S. Army in Afghanistan, which an independent watchdog group, the Military Religious Freedom Foundation, said was a violation of the military's own rules.
Mikey Weinstein, the founder and president of the group, said there is a "complete prohibition of the proselytizing of any religion faith or practice" in Iraq and Afghanistan.
"You see them wearing American helmets. It is obvious they were completely embedded," he said.
When ABC News contacted the Army in Afghanistan, it said it no longer have the records of the evangelicals' embed, which took place more than four years ago. The missionaries said they weren't accompanied by soldiers when they handed out Bibles, but Decker and Scott said the military was aware of the purpose of their trip.
"It wasn't like we were hiding in the back saying we're going to preach," Scott said. "They knew what we were doing. We told them that we were born again Christians, we're here doing ministry, we shoot for this TV station and we want to embed and see what it was like.
"We were interviewing the chaplains and we talked to them. We spoke at the services and things like that. So we did do our mission being over there as far as being able to document what the soldiers go through, what it's like in Afghanistan," he said. "So I could say that we were on a secular mission as well as far as documenting. I would say we were news reporters as well, we were delivering news of what was actually happening there, but we were also there to document the Christian side."
He added that as Christian journalists they should have the same rights as other networks, and that the military didn't facilitate their actions or preaching.
"If, for example, if I wasn't allowed on base I would feel like my freedoms were being restricted. Just because we were Christians and I am documenting for a Christian reality TV series, that I should have the same right?" Scott said. "That's like saying I'm not going to let al-Jazeera report anything because their reporter is very religious."
Weinstein, however, charges that simply by having missionaries walking amongst the troops presents a national security threat. The U.S. Army might be viewed by local Afghanis as a Christian army, he says, inciting suspicion and possibly violence from those who view that as a threat to Islam. "That is what our fight is about," Weinstein says. "It's wrong and this is something that is emboldening our enemy and it is killing and maiming our American Military and it has to stop."
There are also larger concerns about Scott and Decker's work. Critics say when missionaries evangelize to remote tribal groups, they risk destroying ancient cultures.
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.'"