The Ribat, a muslim model for Christian religious militia such as the Knights Templar?

"The Templars were the first military order,  a completely new, hybrid type of organization merging the hitherto mutually exclusive spheres of chivalry and monasticism into a single institution of sacred violence.a Beforehand, chivalry and monasticism had been regarded as incompatible spheres. It was only at the beginning of the nineteenth century that the suggestion was first made that this order was inspired by Muslim institutions.

Introduction to the Middle Ages: Barbarians, Christians and Muslims - quotes

"The Middle Ages were not only a period of European civilization. There was the western medieval period and that of the Eastern Empire, which still survived among the splendours of Byzantium for 1000 years after the fall of Rome. During those same centuries a great Arab civilization flourished, while in Europe there was a more or less clandestine, but very lively Jewish culture. The boundaries between these different cultural traditions were not as marked as people think today.

March 18, 2016 - 702nd Commemoration death of Jaques de Molay

On March 18, 2016 we commemorated the 702nd anniversary of the death of the last official Grand Master of the Knights Templar, Jacques de Molay. De Molay, born in 1244 was put to death in Paris by the King of France on 18 March 1314. He was the 23rd and last Grand Master of the Knights Templar, leading the Order from 20 April 1292 until it was dissolved by order of Pope Clement V in 1307.

Though little is known of his actual life and deeds except for his last years as Grand Master, he is the best known Templar, along with the Order's founder and first Grand Master, Hugues de Payens (1070–1136). Jacques de Molay's goal as Grand Master was to reform the Order, and adjust it to the situation in the Holy Land during the waning days of the Crusades.

Death-site plaque of Jaques de Molay on Isle des Juifs, Paris
As European support for the Crusades had dwindled, other forces were at work which sought to disband the Order and claim the wealth of the Templars as their own. King Philip IV of France, deeply in debt to the Templars, had De Molay and many other French Templars arrested in 1307 and tortured into making false confessions. When de Molay later retracted his confession, Philip had him executed by burning upon a scaffold on the Paris Ile des Juifs in the River Seine on 18 March 1314.

source text and illustrations wikipedia.org

12th century Templar ecclesiastical privileges, powers and immunities by papal bull "Omne Datum Optimum"

In 1172 AD Pope Alexander III famous bull, omne datum optimum, confirming the previous privileges of the Templars, and conferring upon them additional powers and immunities, was published in England. 

The Hospitaller Order - from caring to fighting

"The first authentic notice of an intention on the part of the Hospitallers to occupy themselves with military matters, occurs in the bull of Pope Innocent the Second, dated 1130 AD. This bull is addressed to the archbishops, bishops, and clergy of the church universal, and informs them that the Hospitallers then retained, at their own expense, a body of horsemen and foot soldiers, to defend the pilgrims in going to and in returning from the holy places. 

Templar privileges, powers and immunities set by papal bull "Omne Datum Optimum" 1172 AD

In 1172 AD Pope Alexander’s famous bull, Omne datum optimum, confirming the previous privileges of the Templars, and conferring upon them additional powers and immunities, was published in England.