Indeed one's faith in one's plans and methods is truly tested when the horizon before one is the blackest.

Catholic Priest                          

Selected Works: 

Testament: Memoir of the Thoughts and Sentiments of Jean Meslier - 1729.  Published in English translation by Michael Shreve for the first time -  November 1, 2009.

Le Testament, French Edition - 1974.

Superstition in All Ages, Common Sense - not written by Jean Meslier, but by Baron d'Holbach. This book was published under the name of Meslier, becasue of severe restrictions on the press in the 18th century.

Baron d'Holbach published virtually all of his work under the names of famous dead people.

Voltaire published his own expurgated version as Extraits des sentiments de Jean Meslier - First edition, 1762.                          

When Meslier died, there were found in his house three copies of a 633-page manuscript in which the Catholic priest denounces organized religion as "but a castle in the air" and theology as "but ignorance of natural causes reduced to a system".

http://en.wikipedia.org/wiki/Jean_Meslier

Voltaire published his own expurgated version as Extraits des sentiments de Jean Meslier - First edition, 1762.

Voltaire's edition changed the thrust of Meslier's arguments (or drew on other Extraits which did this)so that he appeared to be a deist - like Voltaire- rather than an atheist.

The following passage is found at the end of Voltaire's Extrait, and has been cited in support of the view that Meslier was not really an atheist. However, the passage does not appear in either the 1864 complete edition of the Testament, published in Amsterdam by Rudolf Charles, or in the complete works of Meslier published 1970-1972.
'I will finish by begging God, so outraged by that sect, to deign to recall us to natural religion, of which Christianity is the declared enemy. To that simple religion that God placed in the hearts of all men, which teaches us that we only do unto others what we want to have done unto us. Then the universe will be composed of good citizens, of just fathers, of submissive children, of tender friends. God gave us this religion in giving us reason. May fanaticism no longer pervert it! I die more filled with these wishes than with hopes. This is the exact summary of the in-folio testament of Jean Meslier. We can judge how weighty is the testimony of a dying priest who asks God's forgiveness.

Michel Onfray, In Defense of Atheism, wrote - For the first time (but how long will it take us to acknowledge this?) in the history of ideas, a philosopher had dedicated a whole book to the question of atheism. He professed it, demonstrated it, arguing and quoting, sharing his reading and his reflections, and seeking confirmation from his own observations of the everyday world. His title sets it out clearly: Memoir of the Thoughts and Feelings of Jean Meslier; and so does his subtitle: Clear and Evident Demonstrations of the Vanity and Falsity of All the Religions of the World. The book appeared in 1729, after his death. Meslier had spent the greater part of his life working on it. The history of true atheism had begun.
Translation by Jeremy Leggatt.