MEMPHIS, Tenn. — Nathan Knight was 11 and selling newspapers when he met the Rev. Dr. Martin Luther King Jr. back in 1958.

It was on the campus of Bennett College, a historically black school for women in Greensboro, N.C. He said he sold King a copy of a now-defunct newspaper called the Future Outlook for 15 cents. King gave him a quarter and told him to keep the rest.

"I had no idea who this man was at that time," Knight, now 71, told me on Wednesday. "The only thing I knew is that I had gotten a great tip from this guy."

Later that day, Knight was still selling copies of the newspaper and happened by a room where King was giving a speech.

"I was struck. I tried to sell my papers but I kept looking at him," said Knight. "There I was listening to this dynamic man and selling newspapers.  I told everybody about the speech. There were many that said, 'He's a rabble rouser. You shouldn't have been there.' "

Naysayers or not, hearing King speak that day changed the course of his life because it ignited a fire in him that still burns.

When I caught up with Knight on Wednesday, he was standing near a sign for the old Lorraine Motel, the Memphis property where King was staying on April 4, 1968, the night he was assassinated.

He had been drawn there for the same reason the Rev. Jesse Jackson, I, and so many others were  – to pay homage to the slain civil rights leader's memory and legacy. Thousands had converged on this predominantly black Southern city for activities surrounding the 50th anniversary commemoration of King's death. He was assassinated here while agitating on behalf of striking black sanitation workers – two of whom had been crushed to death earlier that year.

There were days of activities leading up to Wednesday – the highlight of which was the ceremonial ringing of a bell at 6:01 p.m., the time that King was fatally wounded.

In a crowd of thousands, Knight stood out. He was wearing a pair of faded denim overalls and clutching a folded American flag that he'd brought with him in honor of friends who had died and couldn't make the pilgrimage to Memphis marking the 50th anniversary commemoration. I walked over to him because he looked like some of the farmers and other agricultural workers you see in old black-and-white photos from the civil rights movement. He had eyes that looked as if they'd seen some things, as they say.

After that fateful meeting with King, Knight went on to participate in desegregation protests, including those around the lunch counter sit-ins at the F.W. Woolworth store in Greensboro.

"My life was changed," he told me, as streams of people passed by us to stand in front of the motel balcony where King was when he was mortally wounded by a single gunshot.

Knight, now president of the DeKalb County (Ga.) Southern Christian Leadership Conference, smiled a little when he told me about meeting a civil rights worker while in police custody after a protest. He's been married to Delores Knight for 51 years now.

"She was my companion in that dark moment in my life," he added. "We protested many days since that time."

As we talked, another speaker was addressing the crowd outside the Lorraine Motel, which is now part of the National Civil Rights Museum. But I was more interested in listening to Knight talk about various boycotts he's waged against fast food restaurants and grocery stores that poorly served communities in Atlanta, where he lives.

"This is my life," he told me, passionately.

I could have stood there in front of that old motel and spoken with him all night about his adventures with the iconic Southern Christian Leadership Conference. So many stories. So much wisdom.

Like many of those whom I spoke with at the event, he said he felt inspired by the high school students from Parkland, Fla., who led a major march to Washington, D.C., last month to agitate for tighter gun laws in the wake of the bloody shooting at their school and by Black Lives Matter activists who protest against police brutality.

"They are trying to make a difference," Knight pointed out. "I have faith in them. I believe they are going to make that difference. I think they are going to stand up and be what we were in 1960. They're going to do it in 2018."