Pope Francis has called pornography a work of the devil and warned Christians to reject this and other temptations accessed through the internet.

"Any cellphone has access to this brutality, this language of the devil," the Pope said at the weekly audience in St. Peter's Square on Sept. 25.

Francis said while modern technology has many positive resources to appreciate, he noted, it also allows the devil to tempt us, "and many people fall for it."

"Think of internet pornography, which there is a thriving market behind," he continued. "We all know the devil works there."

He told thousands at the Vatican, that pornography "is a very widespread phenomenon, but one that Christians must be very careful to guard against and strongly reject."

At his Wednesday audience on the eve of a four-day trip to Luxembourg and Belgium, the pontiff spoke softly and had to pause occasionally to cough after canceling two meetings earlier in the week due to suffering from "flu-like" symptoms, according to the Vatican.

Pope Francis offered advice for avoiding sin when tempted by the devil, including not to believe in superstition or to become involved with occultism, spiritualism, astrologers, sellers of spells and amulets, and satanic sects.

He said these are prevalent despite modern society's denial of the existence of Satan.

The Pope said, when temptation hits, to ask the Virgin Mary for help and to immediately send the devil away — "do not dialogue with the demon."

"Be careful because the devil is clever, but we Christians, thank God, are smarter than he is," the Pope reminded.

Quoting from a priest in the Church, St. Caesarius of Arles, Francis said: "After Christ on the cross defeated forever the power of the 'ruler of this world,' the devil ... 'is bound, like a dog on a chain; he cannot bite anyone except those who, defying the danger, go near him... He can bark, he can urge, but he can bite only those who want.'"

The Pope added that while it is true the devil is present and working in extreme forms of evil and wickedness in human history, "do not be discouraged."