Pope John Paul 11 flew here today on a mission clearly intended to strengthen and perhaps discipline the Roman Catholic Church in Latin America.

He stepped from his plane to kiss the soil of the western hemisphere, in a gesture of humility that dramatized the importance he attaches to the trip, his first outside Italy since his election Oct. 16.

Then he concelebrated mass in the city where the Eucharist was first celebrated in the western hemisphere 486 years ago.

There was a tumuituous welcome for "Papa Juan Pablo II," the first pope to come to the island of Hispaniola, and the second to visit Latin America.

Women threw kisles from balconies. Children waved yellow and white papal flags. Youngsters danced in the path of the entourage, slowing the drive from the airport, and a sidewalk band added to the festival spirit as church bells clanged.

His mission was outlined in specific terms as he stepped from the Alitalia DC-10 to be greeted by President Antonio Guzman.

Using the third-person voice, he declared: "The pope wants to be close to this evangelistic church, to further its efforts, to bring new hope to its hopes, to help it discern its path better, empowering or modifying its advantages so that it can be more faithful each time to its mission."

The message indicated that church discipline will be a theme of his meeting with the Latin bishops, an indication also supported by some of his comments to reporters aboard his plane.

The 58-year-old Polish pontiff seemed tireless and ebullient during the long day. He spent more than an hour with reporters on his plane, saying at one point that he will visit the United States "but I do not know when," and continued to work with apparent relish during a 10-hour program here.

Tens of thousands had lined the roadway from the airport to the catchedral, the first to be built in the western hemisphere. There he met the bishops of the region, including a special delegation of four cardinals fro mthe United States. With only a brief rest at the residence of the papal nuncio, he continued on to a sunset mass before an estimated tinued on to a sunset mass before an estimated 30,000 in Independence Square.

Another mass and special visits, including one to the slums of the city, are scheduled for Friday before his mid-morning departure for Mexico City.

There was a special sense of church history as he entered the simple splendor of the cathedral, built here at the beginning of the 16th century. The entry procession took him past the tomb of Christopher Columbus.

Columbus brought no priests with him on his first voyage, in 1492. But on his return the next year there were, by historian Samuel Eliot Morison's estimate, as many as 12 aboard the 17 ships, and thus Santo Domingo became the site of the first mass, the first cathedral, the first seminary, the first shrine to the Virgin Mary and the first university in the western hemisphere.

Roman Catholicism has grown to dominate Latin America since that beginning, but the Latin church is deply divided over its proper role in the face of injustice, oppression and unrelieved poverty.

An increasing number of priests and bishops have become politically active, many interested in socialism many critical of capitalism, many embracing a new social activism they call the "theology of liberation."

The pope spoke of these things to reporters during his flight. No official transcript was made as he spoke in at least six languages. Some of the quotes were captured on tape recorders. Others were pieced together by reporters and may not faithfully reflect the full views of the pope.

His remarks suggested that he may carry to the Latin American bishops gathered in Mexico an appeal for more caution and less political activism.

He referred to the theology of liberation as "a little theology but more ecology than theology." In his homily at the mass here he called for "liberation from everything which oppresses man but which above all is liberation from sin and wickedness."

The pope rejected socialism that preachees atheism. Perhaps thinking of the experience of his homeland, Poland, where church activity is circumscribed by the Communist government, he expressed skepticism about socialist states that promise freedom of religion, saying that the real test is not the promise but the performance.