As his general audience came to a close Wednesday, Pope Francis praised Aristides de Sousa Mendes, a Portuguese diplomat who helped tens of thousands of Jews and others to flee from advancing Nazi forces.

"Today is the 'Day of Conscience', inspired by the witness of the Portuguese diplomat Aristides de Sousa Mendes, who around 80 years ago decided to follow the voice of his conscience and saved the lives of thousands of Jews and other persecuted peoples," Pope Francis said June 17 in the Library of the Apostolic Palace in the Vatican.

In 1940, Sousa Mendes served as the Portugese consul in Bordeaux, which received an outpouring of refugees feeling the Nazi regime. Many of them sought refuge in Portugal, a neutral nation in World War II, which offered the possibility of safe travel across the Atlantic.

Overwhelmed with refugees, the Portugese government issued a directive that barred refugees from entering the csountry. The directive especially targeted those who could not return to their country of origin, which made it impossible for Jews to obtain a visa, according to a biography from the Sousa Mendes Foundation.

Confronted by the suffering of the refugees, Sousa Mendes found that he could not obey both his conscience and this directive.

Shortly after the directive was announced, Sousa Mendes befriended Rabbi Chaim Kruger, a refugee and father of five. Sousa Mendes tried to convince Kruger to take shelter in his own home.

But Kruger refused, instead going to the streets surrounding the synagogue with the rest of his brethren. The only way he would accept Sousa Mendes' help was if all of the refugees could receive vias, too.

Recounting his encounter with Sousa Mendes, Kruger said that a deputy standing nearby warned Sousa Mendes of the consequences of this action, but Sousa Mendes told Kruger to announce to the crowds that anyone who wanted a visa would receive one.

"All the refugees got visas and he sat all day long and signed them," said Kruger, according to the World Holocaust Remembrance Center. "I helped him in putting the stamps in the passports and then he would sign. He didn't eat nor drink the entire day until late at night, and within a short time gave thousands of visas until the perpetrators came closer and we had to escape through Spain."

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Sousa Mendes is believed to have granted at least 10,000 visas in June and July of 1940, before being recalled to Lisbon.

Sousa Mendes' act of conscience, for which the "Day of Conscience" is recognized, cost him dearly. He was expelled from the diplomatic corps, and his family at times went to a refugee soup kitchen for food.

Yet his suffering did not compromise the clarity of his conscience.

"I could not have acted otherwise," Sousa Mendes said, "and I, therefore, accept all that has befallen me with love."

Although he died in poverty in 1954, Sousa Mendes has since gained attention as an exemplar of an uncompromising conscience. 

In 1966, Sousa Mendes joined the list of the Righteous Among the Nations, a recognition by Israel of non-Jews who heroically saved Jews during the Holocaust. Portugal posthumously promoted him to ambassador and formally apologized to his family. Postage stamps and statues in memory of Sousa Mendes now proliferate his image.

Pope Francis evoked the memory of Sousa Mendes as an exemplar of upholding one's conscience.

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"May freedom of conscience be respected always and everywhere, and may every Christian give the example of the consistency of an upright conscience enlightened by the Word of God," the Pope said.