After an outpouring of grief culminating in the burial yesterday of the slain Rev. Jerzy Popieluszko, Poland now waits anxiously for the outcome of an internal communist party power struggle.

Only hints of the turmoil inside the party's bureaucratic ranks, precipitated by the police slaying of the priest, have surfaced so far. Five police officers are being held in connection with the case, and one general from the Ministry of Internal Affairs -- the man directly responsible for monitoring church activities -- has been suspended for dereliction of duty.

These developments have raised expectations of more purges to come. But few pieces have been provided to the puzzle of what the plotters had hoped to achieve by eliminating one of the country's most popular clerics. Government officials still appear to be probing for many answers themselves.

The Polish leadership has labeled the tragedy a political provocation against the policies of Gen. Wojciech Jaruzelski. But how deep the conspiracy went and whether its backing extended to the Soviet Union remain the subject of much conjecture by Poles and western diplomats.

The captain and two lieutenants who are suspected of directly carrying out the killing reportedly hoped to cover their tracks while implicating the Internal Affairs Ministry. This scheme has been interpreted by some as an attempt to discredit the head of the ministry, Army Gen. Czeslaw Kiszczak, who is closely identified with Jaruzelski.

Speculation as to who might have devised the attempted setup, if that is what it was, has focused on Miroslaw Milewski, a Politburo member and the party secretary responsible for overseeing the internal security forces.

Milewski and Kiszczak represent different factions in the leadership and are widely believed to be rivals.

Milewski is a career policeman, a 56-year-old apparatchik who has been working in Poland's security services since the age of 16. Kiszczak is a soldier who rose through the military intelligence ranks. He belongs to the team of Army officers that has moved into top party and government jobs since Jaruzelski took over as premier and party first secretary in 1981.

Some party bureaucrats resent the Army's growing role. Some military officers, in turn, have a low opinion of the efficiency and political astuteness of the bureaucrats.

These factions have quarreled over a number of key policies since the crushing of the independent trade union Solidarity three years ago. They differ over how repressive to be toward the political opposition, how accommodating to be toward the Roman Catholic Church, how far to go in decentralizing economic control to revitalize Poland's bankrupt economy and how open a posture to assume in the future toward the West.

Jaruzelski had been able to point to a surface calm in Poland as proof that his approach was working. The attack on Popieluszko is generally regarded here as a bid to disrupt this calm. By rupturing relations between Jaruzelski and the church, according to one theory, the perpetrators had hoped to draw the general back into the fold of his own security services. Another aim may have been to discredit the Jaruzelski-Kiszczak group and thereby curb the power of the Army faction in the leadership.

But if that was the case, the plot has backfired. The government's reaction to the tragedy so far marks a severe setback for the hard-liners.

Jaruzelski has acted swiftly to reassert his authority. A week after the Oct. 19 abduction of Popieluszko, the party's Central Committee gave him authorization to purge the security services and party ranks. The committee resolution specifically praised Kiszczak for his role in solving the killing, while excluding any mention of Milewski.

A possibility the Polish authorities would rather not consider is whether the Soviets were involved at all. Moscow was not happy with Warsaw's tolerance of Popieluszko's anticommunist activities in the capital. The Kremlin's displeasure was made plain in an Izvestia article Sept. 11 that was sharply critical of the Polish cleric.

Soviet pressure may have encouraged what appeared to be a general stiffening of the Warsaw government's line toward the church shortly before Popieluszko's death. In September, Jaruzelski abruptly canceled a planned meeting with Poland's Catholic primate, Cardinal Josef Glemp.

A party report in advance of last weekend's Central Committee meeting showed a toughened stance on church-state relations. Some have speculated that Popieluszko's killing was timed with the Central Committee plenum in mind.

Ironically, church leaders had been trying quietly to defuse the Popieluszko case. Pope John Paul II had invited the militant priest to Rome to study. Although church accounts differ on whether Popieluszko had accepted, he was seriously considering the option before his death.