The traditional view of priestly abstinence as a ' godly calling' has been challenged by new evidence from Latin commentators of 1000 years ago.
Dr Conrad Leyser from The University of Manchester says the vow of celibacy in the Catholic clergy can instead be traced to attempts to safeguard church property and keep tabs on careerist clerics.
According to Dr Leyser, who is based in the Centre for Late Antiquity in the School of Arts, Histories and Cultures, the 1137 rule of celibacy can be traced to a period of upheaval beginning with the trial of Pope Formosus' corpse in 897.
The Catholic establishment tried Formosus' dead body for " illegally" leaving his post as Bishop and seeking promotion to the papacy precipitating clashes over attitudes to careerism and trustworthiness of the clergy.
The conflict escalated in the following decade with the election of Pope John X, rumoured to be the lover of Theodora, the most powerful noblewoman in the city of Rome.
He said: "These historical events give a strong case to those arguing for abandoning the vow of celibacy as a way to reverse declining numbers of priests.
"If the Church is to find a way of reversing this decline - then arguing that celibacy is 'god given' holds no water at all as it is not .
"The Pope himself has recognised that celibacy is a late addition to Catholic tradition.
"Celibacy was created as a mechanism to help carve up church wealth between lay people and priests during a period of upheaval.
"It was a way of stopping priests from siphoning off church resources to their wives and children and really went hand in hand with a new view of what the clergy should be.
"The view of the priest as shepherd in charge of his flock changed to seeing the clergy as part of a hierarchical and institutionalized structure.
"Celibacy was one way to show communities they could trust this newly professional clergy and that priests were not in it for their own gain.
"The period of 897 to 1049 is seen by many Catholic historians as the worst point in papal history.
"But really, it was a formative period which lay the groundwork for the Clergy of today.
Dr Leyser carried out the research over 18 months in Germany, with support from the Humboldt Foundation, and the Arts and Humanities Research Council.
He added: " The traditional view argues that celibacy gradually gained ground over the 1000 years following the letters of St Paul, which are often taken as the first major Christian statement on sexual abstinence.
"But as other scholars have shown, Paul's main message was: the end of the world is coming, don't try to change your sexual status, because it's not important and there isn't time!
"The view that the celibacy of the clergy was an inevitable development doesn't stand up to scrutiny. There were some calls for clerical celibacy from the 380s onwards, but these never added up to a coherent campaign.
"Indeed, in the centuries leading up to the dead pope trial of 897, married priests and even married Popes were widely accepted - it was common practice.
"It was only after the controversies of the tenth century that attitudes fundamentally changed."
Source: University of Manchester
Explore further: Sniffing out a partner at a London pheromone party