ROCKFORD, Mich. (WOOD) — A Grand Rapids man is proving that determination knows no bounds, walking for the first time in more than 15 years.

David Worst, 35, suffered serious injuries in an accident when he was 5 months old. He was in his first wheelchair by the age of 4.

Now, he’s back on his feet and hopes to inspire others. On Monday, he shared his message of perseverance at his former school, Rockford Christian School.

Some of Worst’s family members joined a crowd of current and former students and staff at the school. They roared with support as Worst stood on his feet and used a walker to stroll through the schools’ hallways.

“I can’t believe I just did that,” Worst told 24 Hour News 8 afterward.

But his Pure Home Health Care physical therapist, Brad Kuipers, said that Worst actually did believe from the start and that’s what made it all possible.

“I’ll tell you, he was bound and determined to do it,” Kuipers recalled.

Kuipers began working with Worst in June. Worst’s father died earlier this year. Amid the heavy loss, he made it his goal to walk again. It would be the first time he walked in 17 years. Kuipers said meeting a goal like this so quickly doesn’t happen every day.

Worst was greeted with water and hugs from students as he finished walking around the school.

“It wasn’t easy,” he said.

Despite a hint of initial doubt, Kuipers saw the extreme potential beaming from Worst’s determination. Worst said he has his faith in God to thank for his focus.

“Never give up,” he said.