Rabbi Shmuley (right), with Israel’s Ambassador to the United States Ron Dermer at the start of Friendship Circle’s Miami to Key West Bike Ride. Photo: Courtesy.

Islamorada, Florida — I now understand the meaning of the blessing that I’ve always heard, “… And may the wind be at your back.”

I’m on a narrow two-lane highway in the Florida Keys. Trucks and cars are veering around me as they race at incredible speeds. I’m on a bike, trying to maintain a good, steady pace. But the wind. Oh, the wind. It’s like a hand pushing my whole body back.

I’ve already done 60 miles, having started at 9 am. I have nearly 40 more to go. There are only three hours of daylight left. I’m utterly unprepared to bike in the dark. No lights. Nothing. I’ll definitely be taken out by a tractor-trailer. I’d better peddle fast or I’m toast.

And where is my whole group? Where are the other 50 riders? Don’t tell me I’m last. How embarrassing. Maybe it’s better to be taken out of contention by the tractor-trailer, rather than experience the shame of coming in last.

Welcome to the incredible experience of Friendship Circle’s Miami Beach to Key West bike ride to benefit special-needs children. Friendship Circle is one of Chabad’s best kept secrets. Studies estimate that raising a special-needs child can cost up to $5 million. Parents of special-needs kids struggle just to get by. Along comes Chabad with a lifeline — a national program to recruit volunteers, especially other children who are not classified as special needs, to assist with programming. It’s Chabad at its very best.

The bike rides are fundraisers. And despite my description above of my creaky legs and wobbly knees, it is the experience of a lifetime. One hundred miles a day. Two days. From my old school, the Hebrew Academy, to world-renowned Duval Street in Key West.

As Michael Jackson would have said, the experience is a thriller.

That Chabad and Friendship Circle can organize something this complex is not just impressive but mesmerizing. There are pit stops every 15 miles. What greets you is a giant RV packed with protein-filled goodies so that you can obtain the energy to carry on. Drinks of every variety are present (except the alcoholic kind, which is what I feel I most need.)

I love cycling and I’ve taught all of my kids to ride. We take long rides as a family. But by long, I’m talking 25 miles max. This is four times that in a day. I’ve never done what cyclists call “a century,” 100 miles in a day.

Early in the morning, I have breakfast with Israel’s ambassador to the United States, Ron Dermer, who happens to be visiting Miami. Ron and I grew up together in Miami Beach, and later he became my student president at Oxford University after studying at Penn. Contributing to his life is one of my proudest accomplishments. Ron is a true hero of the Jewish people and one of the Jewish state’s most eloquent defenders on planet earth. Ever the gentleman, as soon as I tell him that in one hour’s time I am joining the bike ride to support special-needs children, he volunteers to walk to the school and help send off the ride.

The participants are blown away that the great champion of Israel in the United States, whom they see on national TV fighting Israel’s battles, suddenly appears to wish them success on their journey. We snap a picture with the ambassador and we’re off.

Is that a rocket pack that those guys who just whizzed past me have? What the heck? What was that?

My nephew and my friend, David, stay with me to make sure I stay alive. Any one of the multiple hazards can finish me off.

There is the Florida sun, far less intense in winter, but strong nonetheless. There are the cars that whizz past once our Florida Trooper escort ceases at the outskirts of Miami. In the Everglades there are the gators. So don’t stop for too long because you don’t want to become lunch. But most of all there is my body, which is being pushed to its limit.

Probably the greatest physical challenge I have ever had in my life was when my wife and I decided to climb Mount Kilimanjaro after a visit to Rwanda at the invitation of President Paul Kagame to promote our organization’s anti-genocide efforts. I will never forget the strain of pushing myself on the final ascent to nearly 20,000 feet and how, on the way down, my legs simply turned to jelly.

This is nowhere near as demanding. But it’s a great challenge, nonetheless.

And what keeps me going? The beautiful weather. The camaraderie of friends. But most of all, the sheer exhilaration of the journey. Young Chabad Rabbinical students zoom up in convertibles to take pictures. A drone flies overheard to film the riders. Chabad’s continued mastery of technology blows me away. And then there’s the knowledge that every 15 miles you’re going to get a treat. So keep on pushing yourself because you’re nearly there.

It’s almost dark and I’m on my last five miles. We stop to pray the afternoon mincha prayer. We continue. There is no way I’m going to allow the last vestiges of light to disappear before I reach our hotel. I up my pace. My nephew follows suit. We are gaining speed, racing against the fading sun. Our goal is just ahead of us. Four miles. Three. Two. And there we are.

We made it. Nearly 100 miles in a day. Tomorrow — repeat — another 100 miles, and we’ll be in Key West.

I quickly discover why they call it a century. It felt like it took one to just to complete the ride.

But complete it I did, thank God. It’s a miracle.

Since I was a boy of nine and first got very involved with Chabad through sleep-away camp, I have been amazed at the inspiration the movement has given me to achieve goals I thought beyond me.

As here, in my 49th year, the Rebbe’s vision of a Jewish people who can achieve absolutely anything continues to inspire and amaze me.

Rebbe, you continue to be a thriller.

Rabbi Shmuley Boteach, “America’s Rabbi,” whom The Washington Post calls “the most famous Rabbi in America,” is the international best-selling author of 30 books, winner of The London Times Preacher of the Year Competition, and recipient of the American Jewish Press Association’s Highest Award for Excellence in Commentary. He will shortly publish “The Israel Warrior.” He is live tweeting his ride to Key West on Twitter @RabbiShmuley.