Latin America's Roman Catholics rejoiced that the new Pope Francis is one of their own, while the world has hailed him as a humble champion of the poor and wished him the strength to lead the Church out of crisis.
Commentators said Francis had a reputation for being as conservative as his predecessor, Pope Benedict XVI, but Latin American Catholics celebrated the fact that the cardinals had, in his words, gone "to the end of the world" to find him.
Latin America is home to 42% of the world's 1.2 bln Catholics and the election of Argentinian Jorge Mario Bergoglio ended nearly 1,300 years of popes born in Europe.
The choice of papal name in tribute to the mediaeval Saint Francis of Assisi, known for a life of poverty and simplicity, also suggested an emphasis on humility from a man known at home for cooking his own meals and travelling by bus.
U.S. President Barack Obama called him "a champion of the poor and the most vulnerable among us".
For Protestants, whose Christian forebears broke with Rome 500 years ago, the World Communion of Reformed Churches wrote to Francis saying: "We are touched by your humility ... The name you have chosen is a sign for us that attention to the plight of the poor and justice for all people will be important for you."
Francis must tackle crises caused by child abuse by priests and the leak of secret papal documents that uncovered corruption and rivalry inside the Church - trouble that Benedict declared in February was, at age 85, beyond his physical capabilities.
Enda Kenny, the prime minister of staunchly Catholic Ireland who has accused the Vatican of hampering an inquiry into child sex abuse by Irish priests, summed up the thoughts of many:
"We pray that he will have the strength, the good health and the spiritual guidance needed to lead the Catholic Church in the many challenges it faces," Kenny said.
BETTER UNDERSTANDING OF ISLAM?
Francis also faces challenges from outside his Church, with the growth of Islam a particular concern in Africa and Asia, and the advance of secularism in its European heartland and beyond.
U.N. Secretary-General Ban Ki-moon said he hoped Francis would continue to promote inter-faith talks.
Russia's Orthodox Church hoped "that relations between the Orthodox and Catholic churches will develop in a positive spirit". It shares Catholics' conservative morality but disputes still strain relations nearly a millennium after the Great Schism split Christianity into eastern and western branches.
President Vladimir Putin said he was sure that "constructive interaction between Russia and the Vatican will continue to develop on the basis of the Christian values that unite us".
The World Jewish Congress offered congratulations and Israeli President Shimon Peres said Francis "comes in the wake of a pope who greatly promoted ties with us". He added: "I am sure that the chosen pope will maintain this course."
Some questioned whether Francis, the 76-year-old son of an Italian immigrant railway worker, was too old to lead a Church that needs to attract younger worshippers to fill emptying pews.
But Father Emmanuel Alfonso, executive director of the Jesuit Communications Foundation, said of the elevation of his fellow Jesuit to the papacy:
"This is a radical change. The majority of Catholics live outside Europe and we have been praying for this."
But there was little or no suggestion that Francis would be any less doctrinally conservative than his predecessors on issues such as artificial contraception, priestly celibacy, female ordination or homosexuality.
"He's not going to be a big liberal; there will not be big changes in Church teaching," said Jesuit Father James Bretzke, professor of moral theology at Boston College.
"He has a reputation of being rather inflexible and staunchly conservative."
Nevertheless, this did not deter those hoping for a more inclusive, democratic church with more obvious appeal to the young.
Helmut Schueller, head of the Austrian dissident Priests' Initiative whose "Call to Disobedience" has challenged Church teachings on priestly celibacy and the ordination of women, said he hoped Francis would invite bishops to "lead the global church in a new and different way".
This meant "decentralising, perhaps 'sidelining' a bit, the central importance of the Curia (Vatican administration), getting help from outside to bring in all of what is going on in the various regional churches".
The Women's Ordination Conference, which campaigns for women to be allowed to become priests, said it hoped that Francis's "sense of justice extends to the women of the Church and their capacity for divine leadership".
However, for now at least, Francis's calm, quiet demeanour mattered more to the faithful than his outlook. A Rome resident named Teresa spoke for many on Thursday morning when she said:
"Yesterday he transmitted such humility, love and brotherhood. He gave all of us great hope and faith."
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