Mr Khashoggi said he was resigning for the good of the newspaper
A leading Saudi Arabian journalist has resigned from his post as editor-in-chief of one of the country's more progressive newspapers.
Jamal Khashoggi was editor of al-Watan which published an opinion piece questioning Salafism, a form of Islam at the heart of the Saudi state.
There is speculation that Mr Khashoggi had been forced to resign.
Mr Khashoggi had clashed with the authorities before with articles on the religious police and women's rights.
The resignation was said to have come as a shock to staff at the newspaper.
The opinion piece by Saudi poet Ibrahim al-Almaee criticised Salafism, a conservative school of Sunni Islam that draws inspiration from the practices of the earliest Muslims.
Saudi Arabia is governed under an austere form of Salafi Islam, Wahabbism.
Salafi Muslims reject popular religious traditions such as the veneration of important Islamic figures and shrines connected to them.
"We believe in al-Watan newspaper, and we believe in reform," Mr Khashoggi said after resigning.
"The newspaper is more important than I am, and I hope it will continue. We may question social issues like women's rights, but we should not have allowed an article to question the essence of faith."
He said he was abroad when the decision was made to publish the article, and he did not agree with the points made by Mr Almaee.
In 2003 Mr Khashoggi was dismissed from al-Watan for criticising a 14th Century Muslim theologian, but returned to the newspaper in 2007.
Mr Khashoggi will keep his position on the editorial board of the paper, and said he would continue to write in support of reform.