World political and religious leaders voiced regret but respect for Pope Benedict XVI's shock resignation Monday, praising him as one of today's "most significant religious thinkers".
From Australia, the Philippines, to Israel and Britain, plaudits for the 85-year-old pontiff, as well as messages of surprise and sympathy for his historic decision to step down citing old age, swiftly poured in.
From his native Germany, Chancellor Angela Merkel expressed the "greatest respect" for Benedict's "difficult" decision to step down on February 28 which, she said, was "for his Church and the people within it".
"He is and remains one of the most significant religious thinkers of our time," Merkel, a pastor's daughter, said.
Describing the move as "eminently respectable", French President Francois Hollande said France "hails the pope who took this decision", while Prime Minister David Cameron said the pope had worked "tirelessly" to bolster Britain's relations with the Holy See.
Italian President Giorgio Napolitano said the pope had displayed "an extraordinary courage" and German President Joachim Gauck, also a pastor, said the move had required "great courage and self-reflection".
In the mainly Catholic Philippines, a spokesman for President Benigno Aquino expressed sympathy and Australian Prime Minister Julia Gillard praised the pope's decision for its "humility".
"On his election, Joseph Ratzinger said he wished to be 'a simple humble worker in the vineyard of the Lord' and in his resignation that humility has been amply demonstrated," Gillard was quoted by Australian Associated Press (AAP) news agency as saying in a statement.
Joseph Ratzinger was the pope's name before he was made pontiff.
From other world religions, Israel's Chief Ashkenazi Rabbi Yona Metzger praised the pontiff for improving ties between Judaism and Christianity which helped reduce anti-Semitism around the world.
World Jewish Congress President Ronald Lauder said Benedict's papacy had "elevated Catholic-Jewish relations onto an unprecedented level".
"No pope before him visited as many synagogues. He met with local Jewish community representatives whenever he visited foreign nations," he said.
The new Archbishop of Canterbury, leader of the world's Anglicans, said he understood the pontiff's decision to step down due to his fading strength.
"It was with a heavy heart but complete understanding that we learned this morning of Pope Benedict's declaration," said Justin Welby, who formally became the spiritual leader of the Church of England last Monday.
But groups representing victims of child abuse in Catholic-run institutions welcomed the resignation.
"This pope had a great opportunity to finally address the decades of abuse in the church but at the end of the day he did nothing but promise everything and in the end he ultimately delivered nothing," John Kelly, of the Irish Survivors of Child Abuse support group, told AFP.
In Australia, the Survivors Network of those Abused by Priests (SNAP) issued a statement saying the pontiff had done little to stop "the reign of terror of child rapist priests", according to AAP.
Pope Benedict was born Joseph Ratzinger in 1927 in the predominantly Catholic southern German region of Bavaria, whose state premier Horst Seehofer said the decision deserved the "greatest respect even though I personally deeply regret it".
Father Adam Boniecki, a close friend of Benedict's Polish predecessor John Paul II, said Benedict had taken note of the end of John Paul's papacy.
"I think that he did not want a repeat of those last dramatic months when the pope was still in his position but practically incapable of fulfilling his functions," he said.
Also in the late pope's homeland, Polish PAP news agency quoted Bishop Wojciech Polak, secretary of the Polish episcopate, as saying: "It's a huge surprise for us all."
"Pope Benedict XVI already asked himself many times whether, due to his age, he still had enough strength to fulfil his duties as Saint Peter's heir," Polak added.
A spokesman for the foreign affairs department of the Russian Orthodox Church said he did not anticipate any major change of course as a result of the pope's resignation.
"There is no reason to expect radical changes in the Vatican's policy or its attitude towards orthodox churches," Russian agency Interfax quoted Dimitri Sizonenko as saying.
In Angola, where the pope visited in 2009, Siona Casimiro, chief editor of the Catholic O Apostolado newspaper, said the decision would "re-ignite the discussion on the possibility of introducing an age limit" on the papacy.
The pope has taken part in 24 official trips abroad since assuming the office in 2005, according to the Vatican website, as far afield as Mexico, Benin, Sydney and Brazil.