Denis Diderot was a prominent Enlightenment philosophe and Editor in Chief of the Encyclopédie, one of the great achievements of the French Enlightenment. Diderot entered wholeheartedly into the project after roughly a year, and soon assumed full control of its development, despite efforts by French censors to ban or curtail its production. Diderot was also a writer of some ability; Jacques le Fataliste et son Maǐtre (Jacques the Fatalist and his Master) was amongst his more formidable works, challenging traditional conventional novel writing and also explored the nature of free will.
Diderot's father was a well-off master cutler in Langres. Although Diderot's first ambition was to be a priest, this idea faded when he moved to Paris to further his education. His father had made arrangements for him to study law, but he disliked this idea. In fact, he disliked the very idea of any profession at all. As a result, his father cut off his allowance and for the next ten years he lived an aimless existence in Paris, doing all manner of menial work. He once had a post as a tutor in the household of a wealthy Parisian financer but abandoned his post, telling his employer "I am a Thousand times too rich and too well off in your house, and must leave it" 
In 1741 he met Anne-Toinette Champion, a beautiful woman who met Diderot's fathers disapproval. He told his father he intended to marry her, causing a major fight between father and son; as a result, Diderot demanded his inheritance, threatening to have his father arrested if he did not receive it. Obtaining royal permission, his father imprisoned him in a monastery. He escaped, laid low and married his sweetheart in secret; this was a decision he would later regret, as it was an unhappy and painful marriage.
Diderot first came to prominence in 1746 with the publishing of his first original work Pensées Philosophiques (Thoughts on Philosophy) which was condemned to be burnt by the Parlement of Paris on the following grounds:
"Presenting to restless and reckless spirits the venom of the most criminal and absurd opinions that the depravity of human reason is capable of; and by an unaffected uncertainty placing all religions on almost the same level, in order to finish up by not accepting any." 
Diderot and the Encyclopédie
The French publisher Le Breton formed a scheme in 1745 issuing a French translation of the British Cyclopedia (1728) of Ephraim Chambers. Le Breton achieved royal permission and recruited noted academic Jean-Paul de Gua de Malves to direct the project as Editor in chief, with Jean d'Alembert to oversee the scientific and mathematical articles. Diderot was invited about a year later to assist and oversee in the translation of the work. De Malves proved to be unreliable however and dropped out of the project, ensuring Diderot assumed his position, while working closely with d'Alembert, who became associate director of the project.
Under Diderot's leadership, the translation soon turned into an original work, an attempt to amass all human knowledge already scattered throughout the world and present it in one concise form - or such was the idea.
Diderot's attitudes towards Christianity
Although in an official capacity Diderot was required to pay a sort of lip service to the Catholic faith, it is quite clear from his personal writings and actions that he was quite anti-Clerical, as many of the great thinkers of the French Enlightenment where. Diderot believed that the Christian religion, similar to other religions in his eyes was largely a history of human credulity and superstition.  Aspects of this anti-religion and anti-clerical stance can be seen in many of the articles in the Encyclopédie, where subtle, clever words reveal a great degree of sarcastic irony. (Examples will be provided asap)
- The French Enlightenment,
- Open University press, 1986; Pg. 26
- Diderot's treatment of the Christian religion in the Encyclopédie; Joseph Edmund Barker; Kings Crown Press, New York, 1941