Roughly 25 percent of the world’s population is Muslim, spread across the majority of countries. These numbers are concentrated in the Arab world (where demographics show populations average 95 percent Muslim) and Asia, including all of Turkey, where 60 percent of the world’s Muslim population lives. Just over 200 of the 232 countries and territories that comprise the current geopolitical landscape are home to Muslims. 
You could circumscribe the globe by connecting all the countries in which a Muslim person resides. Think of an X-Men like cerebrum lighting dots on the globe, with different colors showing how widespread any faith is. The second most abundant would represent those of the Islamic faith, first being all of the combined Christian faiths. The sacred text for those of this faith is the Qur’an – the first edition was printed in Arabic during the 8th century CE and represented through a series of symbols the supposed correct pronunciation and recitation established by the prophet Mohammad.
In Cairo, I visited several of the historical mosques – each reflect the use of Arabic as linqua franca of the faith and the historical language of the country as well as even the history of Egypt in their architecture According to Wordnet , Lingua Franca is properly defined as “a common language used by speakers of different languages” or an inter-language. The prophet spoke Arabic, not because he foresaw the need to have one text which could span the globe, but because Classical Arabic was the language of record of the political force of the time.
The very first mosque established in Cairo – the Al Azhar mosque – is mash-up of the forces that controlled Egypt’s destiny, both prior to its being built in 970 CE and afterwards. The original design reflected classical aspects of earlier Roman and Greek architecture and Coptic Christianity– and additions to the structure came from various sultanates and the Ottoman Empire. Its minarets come from at least three different sultanates, the last added in the 1500 CE. The Ottomans doubled the size of the area to pray in and gated the mosque on three sides (it is adjacent to the Khan El Khalili suq).
In many of Cairo’s mosques, including the Ibn Toulun Mosque (completed just years after the Al Azhar) as well as the Mosque of Sultan al-Muayyad – a monumental mosque built from 1415-1422, Arabic is a design theme. The Qu’ran’s text is incorporated into elaborate decoration, stone work and especially the mihrab, a semicircular space in the wall of a mosque which indicates Qibla – the direction to face when at prayer.
Seeing the sacred text as part of the design and worship, I begin to understand the allure of bringing back a lingua sanctus by Pope Benedict. Arabic, as the language of the Qur’an,can unite people from Detroit, Khartoum and Jakarta under one faith umbrella. Catholicism, though only one of the many Christian denominations, could stand on its own as the third largest religion, after Islam and Hinduism. And, unlike the other two which continue to grow, neither it nor Christianity as a whole, has a uniting language. Vatican II may have brought religion to its people by eliminating an archaic barrier, but it also eliminated the common thread that could connect millions.
 Mapping the Global Muslim Population, The Pew Forum on Public and Religious Life