“Did I teach you anything?” Antoinette Messina asked her former 1st-grade student. “Everything,” said Rony Zeltser. “You taught me everything.”

More than 30 years ago, Messina, now 90, taught the immigrant boy English. Through a twist of fate, Zeltser, now 42 and a physical therapist, is teaching Messina to walk again.

“Then you were the teacher,” he told her recently. “Now, I’m the teacher.”

Zeltser emigrated from Israel in 1985 and spoke only Hebrew. His family settled in Borough Park, Brooklyn, where he was placed in 2nd grade at PS 180. The 7-year-old missed Israel and was frightened. “I didn’t want to be here,” he said. After a few weeks, his mother noticed he seemed “lost.”

“She peeked into the classroom and saw I wasn’t learning,” said Zeltser, so she requested he be put in 1st grade to start at the beginning. “Because that happened, Mrs. Messina was my teacher.”

His mother continued to check on him; what she saw warmed her heart. Messina “really focused on me. She took me under her wing,” Zeltser remembers.

Messina taught mostly younger students and enjoyed helping them realize learning could be fun. “I felt very seriously that you start from the ones that are this high and you pull them up slowly,” she recalled, and “when they would say, ‘I can’t,’ I’d say, ‘Why not? Why can’t you?’”

At a 90th birthday celebration in her Bay Ridge, Brooklyn, home, with John, her husband of 62 years, and their daughter, Catherine, Zeltser told Messina, “You put me on my feet.”

He doesn’t remember many details from 1st grade. “But I do remember her voice, and I remember she did a lot of one-on-one with me. She had a discipline about the way she taught. She had patience, and she made me feel comfortable,” he said.

Zeltser went on to flourish in school, even skipping 4th grade. “Mrs. Messina gave me the foundation and, after that, I just caught up,” he said.

This April 15, Zeltser was assigned a new hospice patient by his employer, MJHS Home Care.

He made two visits before something clicked. “I parked outside her building, and it hit me. It was like a godsent message,” Zeltser said. “I thought, ‘This has to be my 1st-grade teacher.’ ”

Zeltser confirmed his suspicion, and “everyone was in shock we reunited,” he said. “It was my turn to help her.”

He saw Messina for four hospice visits, and she was bedridden when discharged. Over his nearly 20 years in home care, “it’s a scenario I’ve seen way too often,” Zeltser said. “I knew if I stopped seeing her, she most likely would not pull through. I decided to continue volunteer visits and, little by little, I got her walking.”

They began with functional walks, from living room to kitchen, and eventually walked 50 feet together in the hallway. Their month of intense therapy “was crucial to her progress,” Zeltser said.

But his commitment didn’t end there. “My promise to her and the family is that as long as she’s here with us, I’m going to visit,” he said. “She deserves it.”

When he told his mother, “she was crying,” Zeltser said. “Not only was I lost all those years ago, but she was lost, too. She didn’t know what to do with me.”

He blew up an old photo his mother had taken of him and Messina and it “was a great therapy tool,” he said. “If it wasn’t a good day, the picture put a smile on her face. Nine out of 10 times, it changed her mood. It helped me to work with her.”

Messina “didn’t only help me. She had a 40-year career and helped plenty of kids,” Zeltser said.

“I loved teaching,” said Messina. “I took it wholeheartedly.”