On Sunday night, the United States suffered the worst mass shooting in its history at the hands of 64-year-old Stephen Paddock.

The killer, armed with multiple guns and operating from the window of his 32nd-floor Mandalay Bay hotel room, mowed down a sea of concertgoers below, killing 59 people and wounding 527.

The carnage ended only when Paddock shot himself to death just before police broke into his room, according to authorities. Because he was so far away from his targets, there was virtually no chance of a hero in the crowd firing back at Paddock to try and stop his killing spree.

Charl Van Wyk, author of the book "Shooting Back: The Right and Duty of Self-Defense," knows what it's like to be caught in the middle of a mass shooting. He also knows what it's like to save a large crowd from further bloodshed.

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It was July 25, 1993 – a cold winter's night in Cape Town, South Africa. Van Wyk was attending the Sunday evening service in St. James Church, which held about 1,500 people, making it one of the larger churches in South Africa.

Because of the cold and the pouring rain outside, there were only about 1,000 worshippers present on this particular night.

The biblical mandate for armed self-defense – especially in church! Get "Shooting Back" today!

The congregation was listening to a group of young people singing when, all of a sudden, there was a noise at the front door. Four men entered, and Van Wyk immediately thought it was part of a play. He had heard the youth were planning a show in which people acting as police would barge through the door and kidnap some of the youth for the purpose of having a discussion about what would happen if they were no longer allowed to practice their faith in South Africa.

However, Van Wyk soon realized it was not a play. The men, who were terrorists from the Azanian People's Liberation Army, opened fire with automatic rifles, and the panicked churchgoers all hit the floor.

The attackers also carried hand grenades, to which they had affixed small nails to maximize the damage. One 21-year-old worshipper fell on top of a grenade to save the people around him.

Van Wyk hit the floor, too, but it just so happened he was carrying his revolver with him in an ankle holster. He pulled it out and knelt behind a bench.

Aiming as best he could, he fired two shots toward the attackers. However, the attackers were at the front of the church, and Van Wyk was four rows from the back. His little revolver, with its two-inch barrel, was designed for close-range self-defense, not shooting across an entire 1,500-seat church.

So Van Wyk got down on all fours and crawled to an aisle. He discreetly slipped out the back of the church, planning to circle around to the front of the building and shoot the terrorists at close range from behind.

However, as he ran around the corner of the building, he saw the terrorists were already at their getaway car. Unbeknownst to Van Wyk, one of the two shots he fired at long distance inside the church had hit one of the terrorists, and they were already in fast retreat.

One of the terrorists was standing just outside the back left door of the car, staring at the church door through which he and his fellow attackers had just fled. Looking back on the incident later, Van Wyk realized the terrorist was probably waiting for him to come through that door, at which point he would have blown Van Wyk away with his automatic rifle.

But thankfully, Van Wyk was behind the terrorists. He fired another three shots at them with his revolver, and they all jumped into their car and sped away. One of Van Wyk's bullets was embedded in a car door, which later helped police identify the car. Also, blood from the man Van Wyk had hit was on a car seat, which would later help forensics experts identify the terrorist.

In all, the terrorists killed 11 people and wounded 58. The Saint James Church massacre may have reached the scale of the Las Vegas attack 24 years later if not for Van Wyk's courageous and quick-thinking response.

In a recent interview on "The Hagmann Report," Van Wyk emphasized self-defense is not only a right, but a duty for people of faith, as the subtitle of his book states. He said Christians too often misinterpret the Bible to mean they should let the wicked run over them.

"We have a duty to protect the innocent, those whom God has entrusted to us, and so, even referring to Scripture, Proverbs 25:26: 'Like a muddied spring or a polluted well is a righteous man who gives way to the wicked,'" Van Wyk said. "We're not supposed to give way to the wicked. We've got to stand our ground. We haven't been called to be doormats."

Years after the attack, one of the former APLA terrorists stated, "There we thought the church was a gun-free zone, but, boy, did Charl have a surprise for us."

St. James was an English-speaking church, and Van Wyk suspects the APLA thought the congregants would be too liberal to carry guns with them in church.

However, this is not to say Van Wyk never forgave the attackers. It took him a while, but he got there eventually. In the immediate aftermath of the attack, Van Wyk hated the attackers. He told a police psychologist he had not forgiven the terrorists, and he hated them for what they had done.

"This was a real strong, tough, long-winded issue for me to deal with, and ultimately I realized the Scripture says God tells us if we don't forgive others, He's not going to forgive us. And then, what greater love is there than Jesus Christ dying for us while we're sinners? And I realized I needed to forgive these people, but then again, not that I must call for there to be no justice. Justice still needs to be done, but I personally have to forgive them. Being bitter, it only hurts you, the bitter person."

He explained that forgiveness liberated him, allowing him to move on with his life.

"It was a long, hard struggle, but I did forgive them in the end. I ran a beekeeping course for the former terrorists, I befriended them, we sat and discussed all the things that good people in good company don't discuss, like religion and politics and that sort of thing, and it was a really interesting, interesting time of my life."

The biblical mandate for armed self-defense – especially in church! Get "Shooting Back" today!