Pope Benedict XVI has canonised Brazil's first native-born saint, Friar Galvao, to the cheers of up to a million faithful gathered in Sao Paulo.
Believers from across Latin America cheered and waved flags
The Pope announced the sainthood from a throne flanked by bishops and choirs, and overlooked by a giant wooden cross.
The Church has attributed two miracles to Friar Galvao, an 18th Century monk who is still seen as influential.
The open-air Mass marks the highlight of the Pope's five-day visit to the world's most populous Catholic nation.
Hundreds of thousands of believers from across Latin America cheered and waved flags at Sao Paulo's Campo de Marte airfield. Many had spent the night there.
The BBC's Gary Duffy in Sao Paulo says the Catholic Church in Brazil is hoping that the Pope's visit and the canonisation will help reinvigorate the local church, which has lost millions of faithful in recent years to evangelical churches.
During the Mass, the 80-year-old pontiff encouraged his listeners to follow the example of the new saint by helping the needy "in an age so full of hedonism".
He lauded Friar Galvao as a model of rectitude and humility, and went on to criticise the elements of the media that ridiculed the sanctity of marriage and virginity before marriage.
After canonising Friar Galvao, the Pope also hugged Sandra Grossi de Almeida and her seven-year-old son, Enzo.
She is one of two Brazilian females who the Church says are evidence of divinely inspired miracles that justify Friar Galvao's sainthood.
Friar Galvao is remembered for producing Latin prayers written on tiny balls of paper that, when swallowed, had the apparent effect of curing a range of ailments.
After taking one of these pills, Ms Almeida, who had a uterine malformation that should have made it impossible for her to carry a child for more than four months, gave birth to Enzo.
Friar Galvao is also certified by the Church as healing a four-year-old girl said to have been considered incurable by doctors.
Following the Mass, the Pope met some 430 Brazilian bishops at a Sao Paulo cathedral.
Another highlight of the Pope's trip comes on Sunday, when a crowd of at least 350,000 people is expected to celebrate Mass in Aparecida, where the Pope will also take part in a conference of Latin American bishops.
The forum, the first for 15 years, will bring together nearly 200 bishops and cardinals from Latin America and the Caribbean to set out the Church's agenda and future policies in the region.
'Sheep without a shepherd'
On Thursday, the Pope received a rapturous reception from an audience of tens of thousands of young people gathered at a Sao Paulo stadium.
His address focused on what he called the "snares of evil" - pre-marital sex, drug use, corruption, violence and the temptations of wealth and power.
He urged the young to avoid these and asked them to "be promoters of life, from its beginning to its natural end".
The Pope sparked controversy as soon as he arrived in Brazil on Wednesday by stressing his strong opposition to abortion, the subject of intense debate in the country, where some Brazilians are pushing for the legalisation of terminations.
The World Health Organisation estimates that illegal abortions numbered more than a million in Brazil last year alone.