Vatican City, February 18 - Pope Benedict XVI has said he will be "hidden from the world" when he steps down as pontiff and will spend his life "retired in prayer". But in a sense the 85-year-old German pope is already having a taste of what the future holds for him after entering a Lenten spiritual retreat that will last until five days before he leaves the papacy. The retreat at the Vatican's Apostolic Palace was already scheduled to take place before Benedict shocked the world a week ago by announcing that he did not have the mental and physical strength to continue in a role that is traditionally for life. The last time a pope quit voluntarily was over 700 years ago, in 1294, when Celestine V vacated the post after only five months in it. After explaining at a series of meetings last week that he made the decision for the good of the Church, Benedict saw no reason to change his plan. The retreat started Sunday evening and will last until Saturday, February 23, when Benedict is scheduled to meet Italian President Giorgio Napolitano. The pope, who is set to step down at 20:00 local time on February 28, will hold no audiences during it. So this week's general audience, on Wednesday, has been called off. He is on the retreat with members of the Roman Curia, the administrative apparatus of the Holy See and the Church's central governing body, and of the Pontifical household. The retreat is being held under the direction of the president of the pontifical council for culture, Cardinal Gianfranco Ravasi. Ravasi, who is seen as one of the possible candidates to be the next pope, has prepared a series of prayer meditation "exercises" for the retreat. "The Holy Father gave me the job of preaching the spiritual exercises in the Vatican," Ravasi said. "I think that doing the exercises at this time is a way for us to liberate the soul of the soil of things, including the mud of sin, the sands of banality, the nettles of chatter that occupy our ears uninterrupted, especially at the moment". Vatican radio said it will put podcasts of the meditations on its website so the faithful can download them and listen to them on computers, smartphones and MP3 players. In the first on Sunday, Ravasi used a biblical image to portray Benedict's role in the Church after he steps down, Vatican radio reported. Ravasi compared the outgoing pope to Moses praying for the Israelites on a mountain while they fought in battle against the Amalekites in the valley below. "This image represents the main function - yours - for the Church, that of intercession," Ravasi said. "We will stay in the valley, the valley where there are the Amalekites, where there is dust, where there is fear, terror, nightmares, but also hope, where you have been in these last eight years with us," he said. "From now on though, we will know that your intercession is there on the mountain for us". The outgoing pope will celebrate his final Sunday Angelus prayer service on February 24 and hold his last general audience before what is expected to be a massive crowd on February 27. After stepping down, Benedict will stay at the papal summer residence at Castel Gandolfo outside Rome before moving to a monastery inside the Vatican that is currently being renovated. The papal conclave of cardinals to elect a new pope is expected to start by the middle of March.