DALLAS - As horrific as the mass shooting at a Baptist church in Sutherland Springs, Tex. was, it could have been even worse had it not been for Stephen Willeford and his AR-15.

His house is not far from the First Baptist Church, where Devin Patrick Kelley entered that November 2017 morning, bent on destruction. Willeford's daughter was in the kitchen washing dishes when she heard what sounded like gunfire and rushed to get her dad.

"Especially in a place like Sutherland Springs, it’s hard for your mind to wrap around what’s really going on," Willeford said. "I was in quite denial."

The former NRA firearms instructor quickly realized what he was hearing. He went to his safe to gather up his firearm and ammunition and ran toward the scene without even stopping to put on shoes.

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"I yelled out. It was the holy spirit calling out the demon in him," said Willeford, who shared his story during the National Rifle Association's 147th Meetings and Exhibits, speaking during the Leadership Forum and later from the exhibit hall floor. "As I yelled he came walking out of the church and engaged me."

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 Texas Department of Public Safety via AP

Credit: Jennifer Brett

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Credit: Jennifer Brett

Kelley, right, purchased weapons including the Ruger AR-556 rifle used in the church shooting legally but should not have been able to do so.

He had been court-martialed in 2012 for assault on his spouse and her child while serving in the U.S. Air Force, which did not submit Kelley’s criminal history despite being required to do so by Pentagon rules.

The error meant Kelley's criminal history did not appear on background checks that are conducted on potential gun buyers, and he was able to legally purchase four weapons even after his court martial and dishonorable discharge.

The Air Force pledged a  "complete review of the Kelley case by the Air Force Office of the Inspector General" after the massacre.

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No one has uttered Kelley's name here but Willeford's heroics have been hailed repeatedly.

"His quick action saved countless lives. Stephen is the very definition of a good guy with a gun," said Chris Cox, executive director of the NRA Institute for Legislative Action. "The NRA members are the best of the best. We don’t just believe in individual freedom and responsibility we live it every single day. If a deranged monster comes into your church and starts murdering innocent people, your best bet is an NRA member."

Kelley fired at Willeford and hit a neighbor's truck. Then Willeford returned fire.

"He had an AR-15, but so did I," Willeford said. "I hit him in the body armor and that’s when he realized it was serious. The man was a coward. When I hit him, he stopped shooting at me and started running. He got in his vehicle."

Willeford kept firing.

"I put my rifle up where I perceived his head to be and I pulled the trigger. The window collapsed. I wanted him stopped."

As the gunman's car sped off, Willeford made another quick decision and flagged down driver Johnnie Langendorff. The two men didn't know each other but swiftly joined forces.

"That guy just shot up the Baptist church. We have to stop him," Willeford said. Langendorff didn't hesitate, and dialed 911 while he sped after Kelley.

"Tell them to hurry," he remembers telling Langendorff. "I’ve only got two rounds left."

They stayed in the magazine and chamber. By the time law enforcement arrived, Kelley was dead.

"He had killed himself and that’s OK with me," Willeford said. "I don’t have to say that I killed a man. He took the way out that so many of them do. He’s big, bad and brave when he’s shooting people in a church that are defenseless. As soon as he started catching return fire he wanted out."

Cox presented Willeford with a commendation and made him an NRA member for life.