Forgiveness, not vengeance. That’s how Azim Khamisa feels nearly 18 years after his son Tariq was shot and killed in San Diego.

Khamisa's thoughts are captured in his memoir, "Azim's Bardos: From Murder to Forgiveness."

Tariq, a 20-year-old art college student, was delivering pizza one night in Jan. 1995.

He entered an apartment complex, knocking on doors, looking for the person who ordered the pizza, Khamisa wrote. Tariq was getting impatient.

WATCH: Emily Rooney Interviews Azim Khamisa

http://video.wgbh.org/video/2322920251/

It turns out that the address was fake, and that a group of teens from San Diego’s Black Mob had just wanted to lure Tariq to their location so they could rob him.

As Tariq returned to his car, they demanded to have the pizza. He refused, Khamisa wrote, and started to drive away.

That’s when Tony Hicks, 14, shot and killed Tariq. Hicks became the youngest person in California’s history to face adult criminal charges and was sentenced to 25 years in prison.

Hicks is now 33-years-old and essentially grew up in the prison system.

But instead of feeling angry, Khamisa wrote that he realized “there were victims on both ends of the gun.”

“My grief, my consciousness of irreparable loss, was overwhelming. But the emotion of vengeance was not part of the internal jumble I perceived,” he wrote in his memoir.

Khamisa started an organization with Ples Felix, Hick's grandfather. The unlikely duo called it the Tariq Khamisa Foundation, which aims to stop youth violence through mentorship, education and community-service programs.

“The quality of the rest of my life would hinge on how I handled this tragedy,” Khamisa wrote.

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