When it was revealed that a 17th-century nun had written a “Devil letter” containing an odd combination of symbols, it created a sensation.

A 31-year-old nun named Sister Maria Crocifissa della Concezione resided in the Palma di Montechiaro convent in Sicily.

But because it is thought that she was “possessed” and penned a letter on August 11, 1676, she has been a historical figure of fascination.

According to reports, she was discovered clutching a letter with the strange writing on it and with her face covered in ink on the floor of her cell.

According to historical accounts of the event, the 14-line letter was written by the Devil himself, who was trying to dissuade Mary from God.

Archaeologists have been trying to figure out what it means for a long time, and they may have begun to give it some leeway.

Talking to Live Science in 2017, Director of Italy’s Ludum Science Center Daniele Abate said: “When working on historical decryption, you cannot ignore the psychological profile of the writer.”

“We needed to know as much as possible about this nun.”

According to historians, Sister Maria entered the Benedictine abbey at the age of 15 after deciding to dedicate her life to God.

Abate continued: “The letter appeared as if it was written in shorthand.”

“We speculated that Sister Maria created a new vocabulary using ancient alphabets that she may have known.”

Researchers utilized algorithms that scanned shorthand symbols from other languages to determine the actual language in which this message was written.

They discovered that words from ancient alphabets like Greek, Latin, Runic, and Arabic were included in the nun’s letter.

Abate said: “We analyzed how the syllables and graphisms [or thoughts depicted as symbols] repeated in the letter in order to locate vowels, and we ended up with a refined decryption algorithm.”

“We thought we could just come out with a few words making sense. But the nun had a good command of languages. The message was more complete than expected.”

In addition to calling the Holy Trinity ‘dead weights’, the letter also said: “God thinks he can free mortals. The system works for no one. Perhaps now, Styx is certain.”

The Styx is the river that divides the world of the living from the netherworld in Greek and Roman mythology.

According to Abate, there are clear signs in the letter that Sister Maria was dealing with mental health issues.

He said: “The image of the devil is often present in these disorders.”

“We learned from historical records that every night she screamed and fought against the devil.”