Pope Benedict XVI celebrated his first Mass as the religious head of the Catholics at the Vatican's Sistine Chapel on Wednesday.
The Mass was a private ceremony for the cardinals who elected him and was telecast on TV.
Cardinal Joseph Ratzinger was elected the 265th Pope on Tuesday.
The Pope wore golden vestments and a gold and white bishop's miter.
The Pope has been associated with the Vatican for 20 years. He was one of the few members of John Paul II's inner circle.
Pope Benedict XVI, who is the first German to become Pope in almost 1,000 years, was born in 1927.
He was head of the Congregation for the Doctrine of the Faith, the church's chief think-tank that has dominated discussions on sexual morality and birth control and prevented liberals from gaining ground.
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