Going to Israel during a Jewish holiday wouldn’t normally be my idea of a good time. I haven’t set foot in a synagogue since I moved out of my childhood home nearly a decade ago, and many religious holidays – at least in my experience – tend to put too much emphasis on repenting, and not enough on drinking, dancing and setting off fireworks deep into the night.

But Purim – a holiday commemorating a time when the Jewish people living in Persia (modern day Iran) were saved from extermination in the fourth century BCE – is different. The booze-fuelled celebration, which takes place on the 14th day of Adar on the Jewish calendar (sunset of 23 to 24 February this year), is like Halloween, St Patrick’s Day and New Year’s Eve all rolled into one.

So in attempt to be a good Jewish boy for the first time in a long time, I found myself wearing a sombrero and pink light-up glasses on a rooftop in Jerusalem’s ritziest neighbourhood, overlooking the lights of the stacked houses below, taking yet another shot of arak to shouts of “L’Chaim” (cheers, literally “to life”).

Similar in pronunciation (but not in flavour) to Southeast Asian arrack or central Asian aragh (the name for various regional liquors and moonshines), aniseed-flavoured Middle Eastern arak tastes similar to Greek ouzo and Colombian aguardiente, especially when you’re only taking shots of it. The clear, grape-based liquor also happens to be the national drink of Israel – or at least it’s the cheapest and most readily available. And on Purim, Israelis drink a lot of it. Because God told them to.

Before my arak-drenched boozefest commenced, an Israeli friend explained that there are three things you are supposed to do on Purim: read the Megillah (the relevant section of the Talmud, the central religious Jewish text), give tzedakah (charity), and throw on a disguise and proceed to do as the Talmud states: "drink until you can’t tell the difference between Blessed is Mordechai and Cursed is Haman”. Mordechai is the hero of the Purim story, and Haman, the villain.

As a child, Haman had always been portrayed as a mean man who wore a three-cornered hat, which – to me – always meant the Jews narrowly escaped getting kidnapped by a man who had questionable fashion sense. Growing up in the Detroit suburbs, I had never associated Purim with drinking. It had always been a time for playful laughter and bobbing for apples, and the celebration was always reserved for synagogue. But in Israel, all these years later, Purim was all around me. It flowed out of temples and into the bars, in the streets, on balconies and rooftops. I learned that Haman was basically a biblical-age Hitler, and in celebration of being saved from extermination at his hands, people set off firecrackers, dance in costumes and drink quantities of booze that would have made Hemingway think twice.

No longer was it the exemplification of joyful innocence; now Purim embodied a new kind of spirit – one that had killer cleavage, a short skirt and cat ears. And it was way too inebriated to be walking in those heels.

If this is what religious holidays are like, I decided, sign me up.

Generally speaking, Israelis don’t drink much. According to a 2011 study by the World Health Organization, they’re among the most modest drinkers in the world, especially if you exclude Arab countries. But Purim is one of the few exceptions, when rivers of booze seem to gush through the Land of Milk and Honey.

In two weeks of Purim parties, I was asked countless times whether I’ve tried arak and how I liked it (officially the holiday is only one day, but bars and clubs across the country seem happy to extend it as long as possible. Comparatively, the party that opens the Megillah was apparently a bender to end all benders, lasting 180 days.) Regardless of my response, I was handed chasers (half shots) and cups of arak and grapefruit juice, one of the most popular arak cocktails.

Reasonably, I wanted to know why it’s a mitzvah (good deed or religious duty) to drink so much on Purim, but each of the roughly two-dozen people I asked had a different explanation. “On Purim, everything is upside down,” one said. “You can’t understand the level of joy of being saved if you are sober,” added another. “The alcohol and costumes help show you the truth of the spiritual world that lies underneath the physical world.”

My favourite, though, was the idea that “Israelis can’t handle their alcohol, so when we wake up with a hangover, we think about how we don’t want to drink again until next Purim.” Judging by the 6ft man dressed as a panda lying on the ground at my first Purim party; Mario hugging a tree for balance; and a half-dozen other familiar characters seeking similar fates, this theory seemed to have legs.

But I was enjoying the company of a couple hundred others on that Jerusalem rooftop, singing, dancing and rejoicing. I belted a medley from the musical Grease alongside Danny Zuko and Sandy Olsen, and took a shot of arak. I danced with Mrs Claus, Amelia Earhart and a sexily dressed nerd, and took another.

If it was what God wanted me to do, who was I to argue?

Meanwhile, on the streets below, tens of thousands of people in costume ate, drank and made mitzvahs. Fireworks went off throughout the night. People chanted and waved noisemakers. A giant pink bunny jumped onto the hood of a taxi shouting of “Purim Sameach”  (Happy Purim!).

Friday morning, after the debauchery of last year's Purim died down, I also got to see the family-oriented side of the holiday. People were grooving on balconies, enjoying live music on the Ben Yehuda pedestrian mall and slipping prayer notes into the Western Wall. Spider-Man and traditionally dressed Hasidic men prayed side by side. And then the sun went down and the Sabbath began.