(WBIR) As President Obama spoke to the nation Tuesday morning about his plans for executive action on guns, he used an East Tennessee teen's slaying as another reason to act.

Zaevion Dobson, 15, died on Dec. 17 after diving on top of friends to save them from gunfire in the Lonsdale area of Northwest Knoxville.

VIDEO: President's full remarks about Zaevion

"He gave his life to save theirs. An act of heroism a lot bigger than anything we should ever expect from a 15-year-old," Obama said Tuesday.

Dobson's family, who watched the speech together, says the president's tribute was moving.

"He was the baby of the family. He was the youngest. And he turned out to be the biggest and the one with the most courage," said Zaevion's oldest brother Markastin Taylor.

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The president noted Dobson was heading to a friend's house to play video games when the violence occurred and was exactly where any other kid would be on the week before Christmas.

"And then, the gunman opened fire, for no reason. It was random, and that came out of President Obama's mouth and that touched my heart," said Taylor.

Zaevion Dobson was part of the 100 Black Men group in Knoxville. He played a part in initiatives such as "Save Our Sons" and "Stop The Violence" - projects that aim to end the violence that ultimately claimed his life.

"Zaevion was a lamb that was sacrificed so that we could heal and learn and come together," said Rick Staples, the mentee coordinator for 100 Black Men, "Past political agendas, our own egos, and actually work together to save our children and stop this violence."

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President Obama used a Bible verse to further describe Dobson's heroism and sacrifice.

Obama recited, "Greater love hath no man than this, that a man lay down his life for his friends." The verse comes from John 15:13.

"We are not asked to do what Zaevion Dobson did, we are not asked to have shoulders that big, a heart that strong, reactions that quick. I’m not asking people to have that same level of courage or sacrifice or love."

Obama said if Americans can find the courage to vote, get mobilized and organized, Americans can do what a sensible country would do.

"And if we do we’ll leave behind a nation that’s stronger than the one we inherited and worthy of the sacrifice of a young man like Zaevion," Obama noted.

Full transcript of President Obama remarks about Zaevion Dobson:

"And if you have any doubt as to why you should feel that “fierce urgency of now,” think about what happened three weeks ago. Zaevion Dobson was a sophomore at Fulton High School in Knoxville, Tennessee. He played football; beloved by his classmates and his teachers. His own mayor called him one of their city’s success stories. The week before Christmas, he headed to a friend’s house to play video games. He wasn’t in the wrong place at the wrong time. He hadn’t made a bad decision. He was exactly where any other kid would be. Your kid. My kids. And then gunmen started firing. And Zaevion -- who was in high school, hadn’t even gotten started in life -- dove on top of three girls to shield them from the bullets. And he was shot in the head. And the girls were spared. He gave his life to save theirs –- an act of heroism a lot bigger than anything we should ever expect from a 15-year-old. “Greater love hath no man than this that a man lay down his life for his friends.”

We are not asked to do what Zaevion Dobson did. We’re not asked to have shoulders that big; a heart that strong; reactions that quick. I’m not asking people to have that same level of courage, or sacrifice, or love. But if we love our kids and care about their prospects, and if we love this country and care about its future, then we can find the courage to vote. We can find the courage to get mobilized and organized. We can find the courage to cut through all the noise and do what a sensible country would do.

That’s what we’re doing today. And tomorrow, we should do more. And we should do more the day after that. And if we do, we’ll leave behind a nation that’s stronger than the one we inherited and worthy of the sacrifice of a young man like Zaevion. (Applause.)

Thank you very much, everybody. God bless you. Thank you. God bless America. (Applause.)"