Pope Francis has warned Catholic nuns that they must not be led into temptations of escapism or time wasting by modern social media.

He has called for "prudent discernment" when dealing with the digital world.

In a new document on women's contemplative life in the Catholic Church, Pope Francis admits: "In our society, the digital culture has a decisive influence in shaping our thoughts and the way we relate to the world and, in particular, to other people."

Monasteries and convents are not immune from this cultural climate.

"Clearly, these media can prove helpful for formation and communication," he continues.

"At the same time, I urge a prudent discernment aimed at ensuring that they remain truly at the service of formation to contemplative life and necessary communication, and do not become occasions for wasting time or escaping from the demands of fraternal life in community.

"Nor should they prove harmful for your vocation or become an obstacle to your life wholly dedicated to contemplation."

Pope Francis is preaching what he practises. He has nearly 10 million followers on Twitter as @Pontifex but never reads Facebook or Twitter or tweets himself, and follows just the other eight Pontifex accounts in other languages.

He personally steers clear of the internet as much as he can.

Yet is fully aware of its potential and under his leadership the Church's communication capacity has flourished as never before, with this week's World Youth Day celebrations in Poland likely to prove one of the most effective witnesses to these skills in the history of the Church. 

In the document, Vultum Dei quaerere or Seeking the Face of God, Pope Francis says even many who claim to be non-believers acknowledge the heartfelt longing for the transcendent.

He quotes St Augustine: "You made us for yourself, and our hearts are restless until they find their rest in You".

God calls us all to move beyond self-centredness, he writes. The great challenge facing by consecrated people is to live out Christ's life of chastity, poverty and obedience life as "a credible and trustworthy sign". The monastic life must exemplify the values of silence, attentive listening, the call to an interior life and stability.

This will be met with temptations, he says, and beng a nun "can become a spiritual combat to be fought courageously in the name of, and for the good of, the entire Church".

Among the most "perilous" temptations faced by contemplatives is "the midday devil" which tempts to listlessness, routine, lack of enthusiasm and paralysing lethargy, Pope Francis warns. 

He instructs the nuns he is addressing around the world: "Your work should be done carefully and faithfully, without yielding to the present-day culture and its mindset of efficiency and constant activity."

Among the most active nuns on Twitter is Sister Catherine Wybourne, who tweets @Digitalnun.

She has more than 17,000 followers and uses her feed to promote Christ's message to the world. Today she tweeted:

She offers a dignified response to the new document in her blog, iBenedictines.

She says" "Those of you who know our community will appreciate we have some concerns over the 'one size fits all' approach of Vultum Dei Quaerere, but we must not allow such concerns to get in the way of what we are about. We may be small and insignificant, and we certainly aren't holy yet, but that is our aim: holiness. Nothing less will do."