When Bill Haffey runs by Our Lady of Angels Church on Fourth Ave. in Bay Ridge in this weekend’s New York City Marathon, he’ll smile and remember what it was like growing up in the neighborhood so many years ago.

He attended OLA School in the late 1950s before moving out to Long Island. Later along the course, he’ll run through Park Slope and glance up toward Windsor Terrace, where his father grew up. Memories of Brooklyn long ago!

At 70 years of age, Haffey will be running his 68th marathon. It’s a practice he didn’t begin until a life-threatening illness almost took his life before he was 50. He was only 46 when he developed a tear in his esophagus, underwent surgery and then a little later went into cardiopulmonary arrest.

A psychologist who specialized in rehabilitation medicine, Haffey was determined to not only survive, but to thrive. He set out to take better care of himself, eat right, work out and develop a fine-tuned emotional and spiritual life.

In 2005, a friend invited him to join Team in Training that basically teaches people to run long distance and to help raise money for the Leukemia and Lymphoma Society, a mission he will continue in New York.

“New York is a really difficult race,” he said this week from his mother’s home in Connecticut. “The bridges are a bit of a challenge. I’ll take the race as it comes. I keep focused on the people I’m running for. Running is nothing compared to their discomfort and everything they go through in chemotherapy.”

Haffey, a former seminarian for the Diocese of Rockville Centre, and a graduate of Cathedral College, Douglaston, has set a goal of raising $66,000 for his charity and completing the six Abbot World Major Marathons around the world within 18 months. He recently finished the Berlin Marathon in September in a little over four hours. Earlier this year, he ran Boston in under four hours, a feat he hopes to match in New York. In February, he plans to tackle the Tokyo Marathon and then it’s onto London and Chicago.

Haffey, who admits to being goal-oriented, explains that he will have run the big six after his 70th birthday.

“Only a handful of people have done that,” he says with determination. For accomplishing that milestone, he will receive a medal and hopefully will have accumulated the dollars needed to help combat leukemia and lymphoma.

Haffey stays in touch with his Catholic roots by attending Sacred Heart Church in Coronado, Calif., in the Diocese of San Diego, where he and his wife have been active in the choir for many years. He admits he has less time for choir these days because of his running schedule and his work on a book that will detail his drive to improve his life after 50.

A former volunteer with Mother Teresa, he quotes the saint by saying that the world finds Christ through the ways in which we interact with each other.

“I believe we’re here to make life better for everyone so that we can contact with God. My running is simply a way to give back and to find health, physically, emotionally and spiritually.”

To encourage Haffey and donate to his run in New York, log on to www.mycoolimpossible.com.