(Image Source: Wikimedia Commons ) BY DAN KENNEDY ANCHOR JIM FLINK In a surprise announcement, Pope Benedict XVI announced Monday morning he will resign at the end of this month, citing his age and physical fatigue. In a statement released by the Vatican, the 85-year-old pontiff says, “ ...both strength of mind and body are necessary, strength which in the last few months, has deteriorated in me to the extent that I have had to recognize my incapacity to adequately fulfill the ministry entrusted to me.” USA Today says Pope Benedict -- whose real name is Joseph Ratzinger -- has been considering stepping down for months, sourcing the pope’s brother. MSNBC’s Joe Scarborough says while the announcement is a surprise, Benedict’s deteriorating health isn’t. “There were reports even before this resignation that he was really having a hard time physically, lack of energy, lack of strength, a lot of medical problems they’ve added up to him deciding to step down.” On Sunday, a tweet from the pope’s account read, “We must trust in the mighty power of God’s mercy. We are all sinners, but His grace transforms us and makes us new.” The is the first time in six centuries a pontiff has voluntarily retired. A Vatican spokesperson says the decision took even the pope’s closest aides by surprise. The co-editor of CNN’s Belief Blog notes many didn’t expect the 85-year-old to hold the position for the time he has, and what’s more …   “I don’t think many of the cardinals who were voting expected him to still be alive this long. There was talk of him being a transitional pope to the next leader. Someone who could ride things out … ” The archbishop of New York, Cardinal Timothy Dolan, told the Today Show he, too, was surprised but also thankful for Benedict’s seven years of service to the Church. “My appreciation for him which was already high, is enhanced a little bit... That he says you know, I may not be up to it and I perhaps I can best serve Jesus, his church and his people by stepping aside.” All eyes are on the Vatican now as speculation begins over who could become Pope Benedict’s successor. ABC News explains the eligibility.   “The rule is very simple. It says: Any Catholic male who is not married is eligible, though for more than a thousand years, it’s almost always been a Cardinal.” So, who’s next? An analyst for Sky News says there’s speculation about the first black pope since the fourth century. But the lineup of potential replacements doesn’t seem to match that talk. “What Ratzinger has done in the past seven years is pack the ranks of the cardinals with Europeans. and there’s quite a few Italians.” The College of Cardinals is responsible for electing a new pope in a process called a “conclave.” It requires a two-thirds majority to win. Normally, only Cardinals under the age of 80 can vote, so it’s unclear whether the retiring Benedict will have a role in picking his successor.