His wife, two children and mother-in-law were dead - killed by a fighter jet that lost power and by chance crashed through their home and burst into flames.
One day after losing his family, Yoon held a news conference asking guidance from people who have suffered "more terrible things."
"Please tell me how to do it," Yoon told reporters Tuesday, trying to contain his emotions with his pastor, brother and sister at his side. "I don't know what to do."
Yoon, sobbing into a tissue at the foot of his destroyed home, also asked the public to pray for the jet's Marine pilot, who ejected safely from the F/A-18D Hornet after his training mission went awry Monday.
"I don't have any hard feelings," Yoon told reporters, speaking haltingly. "I know he did everything he could."
The military has given no official word on the cause of the crash, but a congressional aide who was briefed on the incident said the pilot had been attempting to land at a nearby base after his right engine malfunctioned. The aide spoke on condition of anonymity because the information was not yet public.
While the pilot was on final approach to the runway, the aircraft also lost thrust from its left engine, the aide said.
Two homes were destroyed and three others damaged in the crash. Four vehicles were burned.
Dawn Lyons, who lives two blocks away, saw the pilot land. "I had heard the noises, and I thought, 'Oh my gosh, could that possibly be the pilot?' And I saw him pick up his helmet and start down the hill.
She told CBS affiliate KFMB-TV that she was the first to speak to the pilot and said while he did not appear to have any injuries, he was visibly shaken.
The pilot said he "felt fine, then my other neighbors came from across the street and had a phone with her and he said, 'Can I use your phone?' But then he couldn’t remember what number he needed to call.
"He said, 'I was flying on one engine for about a hundred miles.'"
On the same street just a few houses away, Amy Sheridan had their own scare when the pilot's seat landed on her backyard fence.
She said authorities warned people not to get too close in the event not all of the ejector seat's rockets had detonated.