Long-hidden secrets of medieval Belgian beer are coming back to life, thanks to clerics at Belgium's Grimbergen Abbey who discovered them in books from the monastery's archives dating back to the 12th century.

Grimbergen Abbey was founded in 1128, and its clerics — who are technically canons regular, not monks — brewed beer there for centuries. They continued even after the abbey burned down twice during medieval wars, rebuilding in 1629 with the mythical phoenix as their symbol (along with the motto ardet nec consumitur, interpreted to mean "burned but not destroyed"). They eventually gave up in 1798, however, when French soldiers destroyed the abbey and its brewery, according to NPR.

Grimbergen Abbey itself was reinstated shortly after the French Revolution, The Guardian reports, but the brewery and its recipes were thought to be lost. While the abbey didn't resume brewing beer, its name may be familiar to modern beer lovers due to a licensing deal that lets Carlsberg sell a beer labeled Grimbergen on the international market.

But now, more than two centuries later, the Grimbergen phoenix is rising once again — and raising a glass to resourceful clerics who managed to save hundreds of books from the abbey's library before it burned down in 1798. The clerics apparently knocked a hole in the library wall during the French attack, then sneaked out a stash of ancient books before the abbey was torched.

Those books were recently rediscovered, but according to the abbey's subprior, Father Karel Stautemas, their ancient wisdom didn't exactly leap off the page. "We had the books with the old recipes, but nobody could read them," Karel said this week in an announcement about the new brewery. "It was all in old Latin and old Dutch. So we brought in volunteers. We've spent hours leafing through the books and have discovered ingredient lists for beers brewed in previous centuries, the hops used, the types of barrels and bottles, and even a list of the actual beers produced centuries ago."

A view of the landscape outside Grimbergen Abbey, which plans to revive its brewery after 200 years. Marian Klerx/Shutterstock

The new microbrewery will be built inside the abbey, reportedly in the same location as the original, and will include a bar and restaurant. It's scheduled to open in 2020, Reuters reports, brewing about 10,000 hectoliters (264,000 gallons) of beer per year. Karel plans to join the abbey's brewing team once he completes a course at the Scandinavian School of Brewing in Copenhagen.

Rather than following its old recipes exactly, the brewery will use them as inspiration, according to newly appointed master brewer Marc-Antoine Sochon. "In those times, regular beer was a bit tasteless," he tells the Guardian, comparing it to "liquid bread."

The new Grimbergen beer will use the same Belgian yeast currently used by Carlsberg, which is financing the project, to give it a "fruitiness and spiciness," Sochon says. The brewery will also try to emulate its old recipes, though, and plans to avoid artificial additives, use wooden barrels for aging and focus on locally grown crops — including hops the abbey has planted in its garden.

"For us, it's important to look to the heritage, to the tradition of the fathers for brewing beer because it was always here," Karel tells Reuters. "Brewing and religious life always came together."