The head of the Russian Orthodox Church has urged monks to turn their backs on the internet, in order to protect themselves from online temptations.
Patriarch Kirill reportedly described the internet as a "hotbed of sin and temptation", and said that monks who forsake worldly pleasures in real life should do likewise on the internet.
However, he also urged priests to use the internet more actively in the course of their holy mission.
Earlier, he told a meeting of the Supreme Church Council that the "instant reaction to trifles" in the modern world, embodied in "the Twitter approach" must not infect the church's online activities.
"We must not use the language of Twitter when we talk about salvation," Kirill said.
During periods of fasting, the church advises the faithful to abstain not only from meat and fish, but also from using social networking sites.
The Russian Orthodox Church is known for promoting a strictly "traditionalist" view of many current social issues, particularly those related to sexuality and gender roles.
Kirill has also criticised feminism as "very dangerous" and that "it is probably not by chance that most feminist leaders are unmarried women".