A week of spirited sermonizing by Pope John Paul II in his native Poland has bolstered hopes and rekindled enthusiasm among Poles, but the showing of pro-Solidarity sentiments that the pontiff's visit generated has rocked the Communist leadership here, raising new uncertainties about the government's future course.

For the moment, authorities insist that they have no intention of changing direction. They will not resume talks with Lech Walesa, the leader of the outlawed Solidarity trade union; they will not allow competitive independent trade unions and, at the same time, they intimate that they will not keep martial law for much longer.

Accusing the western press of exaggerating the political criticisms that were laced in the pope's homilies and overplaying the antistate feelings of the crowd, Warsaw officials continue to argue that their policies are slowly but surely bringing Poland out of its economic and political crises.

But the papal visit has put new pressures on Poland's leader, Gen. Wojciech Jaruzelski, from two opposing sides. On the one hand, it has strengthened the will of Polish society to resist injustice and repression and to fight for Solidarity's ideals, particularly for genuinely independent trade unions.

On the other hand, the political commotion accompanying the visit has given ammunition to Communist Party hard-liners here and in the Soviet Union to use in attacking Jaruzelski's pro-church line and squelching any further liberalizing move.

"There's no return to the ambiguous policies of before the visit," said a senior lay adviser to Poland's Roman Catholic bishops about the political consequences of the pilgrimage. "There will have to be either an authentic reconciliation between the government and society or a return to the Dec. 13 measures," a reference to the imposition of martial law in 1981.

Others are less convinced that the government will tilt one way or another soon. John Paul appeared not to expect any short-term changes in basic conditions in Poland and pitched his message more toward the long term.

He stressed the price of freedom, the rewards of suffering and the need for faith and hope. He also noted Poland's "difficult geopolitical situation" and acknowledged the constraints of being a Soviet ally.

But the pope, making quite clear he is not satisfied with the direction of what the government calls its reform policies, reinforced the groundwork he laid during his first visit in 1979 for an alternate Christian program strong on freedom, conscience and respect for human rights.

He backed the wishes of Polish workers spelled out in the August 1980 agreement with the government that were the foundation for the creation of Solidarity. He also endorsed the repeated appeal issued by the Polish bishops for a blanket amnesty for political prisoners, the reinstatement of those fired from jobs for political reasons and a full lifting of martial law, which was suspended in December.

"For me the whole visit was a blueprint for how things should be done in Poland," said Maciej Kozlowski, a journalist for the leading Catholic weekly, Tygodnik Powszechny. "He said: 'You've done right, you've fought for natural rights without using force, and I'm with you in this fight.' I think the average Pole now feels a lot stronger."

The pope's forthrightness in stating his case surprised even some of his closest friends here as well as veteran Vatican observers, some of whom say they are concerned John Paul may have gone too far and once again stoked the fires of Polish chauvinism against a Commmunist system that cannot be burned away in the short run.

"He gave the Poles new hope," said Hansjacob Stehle, a West German authority on the Vatican's relations with Eastern Europe. "But he also gave them new illusions. I am worried about what will happen next in Poland."

Few expect another Solidarity to appear any time soon. Authorities still have too strong a grip, and Polish society is still too exhausted and splintered after the crushing of Eastern Europe's first sanctioned independent trade union for a new revolutionary movement to gain momentum in this country.

But if economic frustrations are allowed to build up again--and so far, the decrepit Polish economy has shown little convincing sign of revival--any social explosion is possible. While the pro-Solidarity marches of the past week were organized by a hard core who traveled from town to town along the papal route, there was still much evident widespread support and applause for the demonstrators wherever they appeared.

In turn, there are fears that the government may not wait long to launch a new wave of repression, despite strong hints of an intention to lift martial law this summer. The aim of such a crackdown, the speculation goes, would be to reassert Communist authority after the manifestation this past week of the enormous influence of the church.

During the visit, Polish security forces showed remarkable restraint against the demonstrations. This was in keeping with the government's agreement with the church to maintain a peaceful and dignified atmosphere for the papal visit. It should not, however, be taken as a sign of a new period of leniency, although Polish officials must realize that a new round of police actions would jeopardize the rollback of western economic sanctions against Poland that Warsaw desperately seeks and that approval of the papal visit was to facilitate.

A Polish reporter for a Catholic paper told how he was stopped by police in Czestochowa when the pope was there last weekend for wearing an illegal Solidarity pin. He was asked to remove the pin but did not, and an officer snorted: "So you think you can play badminton with us, like the church."

The remark showed the limits of the political contest being played in Poland--the church's privileges are the exception, not the rule. But the church's political power is expanding, and perhaps the most significant political result of the second papal trip to Poland will prove to be the further strengthening of the Roman Catholic Church here under Communism.

For the Warsaw government, accommodation with the immensely popular church is considered a political necessity for motivating society. For the church, cooperation with the authorities means gaining more parish churches, greater circulation of Catholic publications and a say in the shaping of some legislation.

Recently, the Polish clergy had been somewhat divided over what balance to strike between confrontation and conciliation toward the Jaruzelski government. The pope never addressed this problem. Instead of tactics, he outlined values for the church--a more lasting lesson.

He also endorsed explicitly the development of a pastoral church community and, implicitly, similar church groups being formed among industrial workers and youths--which in effect are bringing former Solidarity elements under the church's umbrella. This is a significant trend and potential source of church-state tension.

While the Soviets have appeared more or less tolerant up to now of the deeper Christianization of Poland, they have little interest in having the process spread beyond Poland's borders. Possibly in deference to Soviet sensitivities, the pope this time, in contrast to his 1979 homilies, omitted references to religious developments in other Eastern European states. His focus was fixed on his own Poland.