Motivational speaker Zig Ziglar dies at age 86

Ziglar, who had been suffering from pneumonia, died at a hospital in the Dallas suburb of Plano, said his personal assistant, Jay Hellwig.

With an aim at helping people achieve success in their careers and personal lives, in addition to a focus on Christianity, Ziglar was a prolific speaker who appeared at events alongside world leaders including several U.S. presidents and former British Prime Minister Margaret Thatcher.

"Mr. Ziglar was the same guy behind the closed doors as he was preparing for his presentations to thousands of people that he was when we were sitting at the kitchen table and he was reading the newspaper," Hellwig said.

Prestonwood Baptist Church Pastor Jack Graham, Ziglar's friend and pastor, said Ziglar "truly was filled with faith."

"He was positive. He was hopeful. You just never heard negativity from Zig Ziglar," Graham said. "It wasn't just something he did on a platform. This was who he was. This is how he lived his life. And he helped so many people."

"He was a leader of leaders and a mentor of mentors and all that you can say," he added.

Ziglar started his fulltime career in motivational speaking when he was in his 40s. His first book was "See You at the Top."