Pope John Paul II celebrated the durable faith of Nagasaki's Roman Catholics today in an open-air ceremony where their endurance was tested by snow and subfreezing temperatures.

[After leaving Japan, the pope made a 4 1/2 hour refueling stop in Anchorage, where he met with Catholic and Protestant clergy and said an open-air mass in the 30-dgree temperature for about 40,000 people. Although it was not an official visit to the United States, Secretary of Labor Raymond Donovan was on hand to deliver a message from President Reagan.]

Ending his Asian tour in the city where Catholicism first came to Japan, the pope praised Nagasaki's legacy of martyrdom.

He also praised the 47,000 faithful who braved the weather in a muncicipal stadium. More than 300 people were treated for frostbite, fatigue and fainting spells.

"You are very courageous to have stood up to all this cold and you are worthy of your ancestors, the martyrs," he said.

The pope's face was reddened by the wind and an aide said later that the pope's fingers were "nearly frozen" as he gave communion to 76 persons baptized at the ceremony. At one point he turned to a group of bishops and said, "I hope that all of the Japanese bishops were not frozen to death." a

Nagasaki was Japan's first center of Catholicism and the church thrived here in the 16th century. But in the early 17th century, the shogunate began suppressing the religion.

The pope paid tribute to those who had worshipped secretly during two centuries of suppression.

"By God's grace, the Christians had meditated on the gospel by means of the mysteries of the rosary and they knew about a man a long way away called the pope," he said. "Today he comes to render homage to the tradition of the Christians of Nagasaki and to tell their descendants personally that he loves them in the heart of Christ Jesus."

His 20-minute homily was delivered in Japanese, which he has used in many of his addresses since arriving in Tokyo Monday. He is the first pope to visit Japan.

The demonstration of faithfulness here was the most memorable of his four-day visit, which has been marked by small crowds and indifference from the general public. Only 1 percent of Japan's population is Christian.

Later today, the pontiff visited Nagaskaki's "Hill of Martyrs" where in 1597, on orders of the shogun, 26 foreign missionaires and Japanese follwers were crucified.