It was in the year 610 that the Prophet Muhammad received the first revelation of what was to become the Koran, the holy book of Islam.
According to Islamic tradition, Muhammad was confronted by the Angel Gabriel while in a cave on Mount Hira near his home in Mecca. The angel commanded him to recite what became the earliest revealed words of the Koran.
Muhammad went on to receive the divine messages, verse by verse, until his death in 632.
"A secular interpretation of any sacred text says, of course, that it's a human production," explains Tim Winter, also known under his Muslim name Abdel Hakim Murad, who lectures in Islamic studies at Cambridge University in England.
"But a traditional believing interpretation says that this is the word of God. It's not a work of co-authorship between God and the Prophet. God wrote it all," he adds.
To begin with, the Koran was passed on orally by the Prophet's followers, who learnt it by heart.
And the oral tradition has remained central to how Muslims approach their sacred text, whose name means "the recitation" in Arabic, its original language.
Even today, millions of Muslim children learn it by heart, as I did when I was a child.
Many do so without being able to speak or understand Arabic. And images of very young children swaying in rows at madrassas, learning the text without understanding the meaning, have given rote-learning a bad reputation.
Yet, says Mr Winter, if it is done without harsh discipline, most Muslim adults will be grateful that the sacred text has been drummed into them.
These days, a competitive edge has been introduced to motivate youngsters.
Recitation competitions are held all over the world.
Thirteen-year-old Talha Gulli has high hopes for this year's contest held by the Islam Channel in the UK for children up to 16.
He started learning at the age of five because he was bored, he says.
So if he had to define where reading the Koran comes among the things he enjoys, where would he put it?
"Top," he says, without hesitation.
After Muhammad's death, his followers felt the need to produce a standardised written version of the Koran.
The process of gathering all the revelations, from both written and oral sources, took some time and it was not until around 650, during the reign of the third caliph Uthman, that scholars completed the work.
One of the oldest surviving fragments of the Koran, dating back to the late 7th or early 8th Centuries, is at the British Library in London.
Although the script slants to the right and looks unfamiliar to modern Arabic speakers, the text itself is almost exactly what you would find in a modern printed edition.
The British Library also holds younger copies of the Koran, among them a richly ornate one written entirely in gold, which was commissioned by Sultan Baybars in Cairo in the early 14th Century.
Any representation of the human form has traditionally been discouraged in Islamic art, helping Arabic calligraphy to thrive in its place.
Soraya Syed is one of the few full-time female Arabic calligraphers in Europe.
Even though writing the sacred words is so closely bound up with the Islamic faith, she says she experiences her art as liberating and profoundly universal.
As she showed me how to write a version of the Bismillah - the declaration "In the name of God, the Compassionate, the Merciful" - she revealed something astonishing.
"When you study calligraphy and read how the old manuscripts describe the letters and the proportions, they use the human anatomy to describe the letters," she says.
"So in order for you to understand the letters and how to write them, you need to understand the human form."
So it appears that there is both an absence and a presence of the human form in Islamic art.
Koran in cyberspace
And today, both recitations and sumptuous facsimiles of the Koran are available to download at the click of a button.
"If the Prophet was alive today, he would be using the most modern technology," says Ajmal Masroor, an imam and self-confessed techno-geek. "He was the most modern of men in his time."
Mr Ajmal feels there is nothing irreverent about downloading verses of the Koran, and their translations, onto his laptop or mobile whenever he needs them.
"If people are scared of the modern world, it contradicts the Koranic message of it being relevant for all times," he says.
Razia Iqbal's full report can be heard on the Heart and Soul programme on BBC World Service radio, at 1132 and 1532 GMT on Wednesday, 18 August, or you can listen online here.