Pope Francis faces greatest challenge yet in Asia
Exactly 17 months after his election in Rome as leader of the world's 1.2 billion Catholics, Pope Francis is shifting gear and turning his attention to Asia.
This week, he begins the first of three - and perhaps four - long-distance trips to encourage his flock in the continent that presents the Catholic Church with its greatest missionary challenge in the 21st century.
Although only 3% of the world's Catholics live in the planet's most populous continent, more have been baptised in Asia this year than in Europe, according to Vatican statistics.
Pope Francis is spending five days in South Korea, where the number of Catholics has grown at a giddy rate over the past four decades.
Their number has risen from 2% to an astonishing 11% of the population in a country where Buddhism is still strong and most young people profess no religion at all. Korean Catholics tend to be well educated and form a significant part of their country's political elite.
Pope Francis will beatify and pay homage to the memory of a group of Korean martyrs who died for their faith in the 18th Century.
What distinguishes Catholicism in Korea from other Asian cultures is that Koreans did not wait for foreign missionaries to arrive before they began to convert.
They formed their own church after learning of the foreign faith brought to China at the beginning of the 17th Century by the Italian Jesuit priest Matteo Ricci.
He introduced Western cartography and mathematics to China and his gilded statue still stands proudly today in the compound of the Catholic cathedral in Beijing.
Pope Francis is the first ever Jesuit to have been elected to the papacy, and he has always regretted that health reasons prevented him fulfilling his ambition to travel to Asia as a missionary after completing his priestly training in Argentina.
After South Korea, he plans to visit Sri Lanka in January, and then to fly on to the Philippines, which has a Catholic majority, due to it once having been a Spanish colony. And I understand that a further trip to Japan is on the cards, even though only a minuscule 0.5% of Japanese are members of his church.
In Seoul, the Pope will be meeting several thousand young Catholics from 23 different Asian countries gathered for a Catholic Youth festival.
The numbers will be far, far fewer than the millions who attended his triumphal visit to Rio de Janeiro for World Youth Day in July 2013, his first foreign trip. But the significance of the South Korean event could transcend that mega-meeting.
An invitation to North Korean Catholics (if indeed any exist today) to send a delegation to Seoul was rebuffed by Pyongyang, but members of the Chinese Patriotic Catholic Church are expected to turn up in force.
Pope Francis took over his high office in the same week that the Chinese leader Xi Jinping took over as president in Beijing.
The Pope sent Mr Xi a personal message of congratulations and in return received a polite reply, despite the (for the Vatican) worrisome gap in official relations between the Catholic Church and China since the Communist takeover in 1950.
On his way to Seoul, Pope Francis will fly over the airspace of Russia and China - and he is expected to send a courtesy telegram to both the Russian and the Chinese leaderships while over their territory, as has long been the custom during papal charter flights.
Pope John Paul visited South Korea twice during the 1980s, but each time his plane avoided Chinese air space.
No plans exist for a papal visit to the demilitarised zone which still separates the two Koreas 61 years after the stalemated end of the Korea War.
But just as during his visit to the Holy Land earlier this year, Pope Francis will make a powerful appeal for peace and reconciliation at his final mass in Seoul Cathedral before he returns to Rome.