Smith's final act was helping deliver food to people experiencing homelessness in the South Bay, said Pastor Scott Wagers of CHAM Deliverance Ministry.
"My friend surprised me, he says I have a friend in my truck. Guy gets out, and it's a giant man," Wagers said.
That man was Smith, who arrived with 12 pizzas to distribute. Photos taken during the event are believed to be the last images of him.
"An hour later, my friend called me and said, he's dead in my truck," Wagers said.
MORE: Former NFL defensive lineman Aldon Smith dies at age 36
According to Wagers, the friend had briefly gone inside his home before returning to find Smith unresponsive. He was later pronounced dead at a hospital in San Jose.
"I couldn't believe it. Because the impression I had from him was that he looked healthy, very humble, and wanted to help," Wagers said.
Smith began his football career at the University of Missouri before being drafted by the San Francisco 49ers in 2011, where he played four seasons.
He later played for the Oakland Raiders and was most recently with the Seattle Seahawks, who released him in 2021 during training camp after an arrest.
After emerging as a standout linebacker early in his NFL career, Smith faced legal issues in subsequent years, including multiple arrests related to substance abuse and driving offenses. He was suspended several times.
Wagers said Smith had been working to use his past struggles to encourage others.
"All of us have troubles. We all struggle. But that's the last act of his life. The last picture of his life. He was with us and the last move he made was giving out to the homeless," Wagers said.
The 49ers released a statement following his death:
"We are devastated by the sudden and tragic passing of Aldon Smith," the 49ers said in a statement. "Aldon's undeniable talent and sheer dominance on the field were on display from the moment he joined our organization, having recorded one of the best rookie seasons the National Football League has seen. Beyond his excellence as a player, Aldon will be remembered for his infectious smile that lit up every room he walked into. Our entire organization sends its deepest condolences to the Smith family and all who knew and loved Aldon."
Wagers said Smith's actions in his final hours offer a lasting message.
"His heart is in the right place. His intentions were good, and I know he would help. And he'd want you to help," he said.
No cause of death has been released.