Ayatollah Ruhollah Khomeini, accelerating his preparations to end 14 years of exile and return to Iran this week, said today that his Islamic movement's success in driving the shah from the country "is only the beginning of our revolution."

In a public message to his millions of followers in Iran, Khomeini, who plans to return Friday, spoke of a need for social justice and religious tolerance in the Islamic republic he plans to establish in Iran.

But his message did not fully allay concerns among Western diplomats and minorities in Iran about the nature of the government he intends to lead from the sidelines. While it renewed assurances to Jews and other religious minorities, it contained little encouragement for those whose opposition to the shah is not based on religious grounds.

As translated by an aide, Ibrahim Yazdi, Khomeini told his followers:

"Those who are struggling without belief in Allah are either lying or they will not succeed. I cannot believe anyone who says he will give up his life if he says he does not believe in Allah.... We must please Allah and no one else."

This appeared to be aimed mainly at Tudeh, the Iranian Communist Party, but it also will undoubtedly be troubling to at least some leaders of the main secular opposition coalition, the National Front, who are not Practicing Moslems.

Khomeini spoke of the "faise accusations" spread in the West that his Islamic movement is made up of fanatics and reactionaries.

He said his Islamic government would prize liberty and Iranian national independence. He accused "the superpowers" of having supported the shah and he said the shah "let foreigners dominate our affairs" -- an apparent reference to the United States.

The statements by Khomeini and his closest aides continued to ignore the U.S.-backed government of Prime Minister Shahpour Bakhtiar, almost as if it did not exist. This attitude coincides with an analysis by French officials that the Bakhtiar government will "be popped like a champagne cork" as soon as Khomeini gives the word.

Khomeini's aides announced last night that he will return to Iran on Friday aboard a chartered Iran Air jumbo jet. They said he would go immediately to speak at the cemetery near Tehran where most of his followers who have been killed in clashes with the shah's forces have been buried.

Despite reports yesterday that former U.S. attorney general Ramsey Clark, who was recently in Iran, would meet with Khomeini, there was no indication today that Clark had been in touch with Khomeini or the U.S. Embassy in Paris.

State Department officials in Washington stressed yesterday that Clark was traveling as a private citizen and had no official U.S. role. But it was understood here that the U.S. Embassy in Tehran had told the U.S. Embassy in Paris to expect Clark and that he would try to see Khomeini immediately.

Khomeini's aides have said that their leader's door is open to Clark. But they say they have had no direct or indirect contacts with any U.S. officials. American officials say there have been indirect contacts with Khomeini's movement but that, as one official said in Paris, "they tend to take place in Tehran."

Meanwhile, Khomeini's aides insisted today that there are no negotiations with the National Front, only meetings in Tehran in which Khomeini's followers there inform National Front leaders of the ayatollah's views.

Khomeini has refused the formal participation of any political parties in the government he plans to form. But he has said that National Front leaders could serve on an individual basis, provided they resign from their party positions.

Yazdi said yesterday that the Front, which comprises the political heirs of premier Mohammed Mossadegh, the leftist leader who briefly chased the shah from Iran in 1953, had joined Khomeini's movement. But he added that there was no question of a deal with the political organization, whose leadership largely represents the urban middle class.

Khomeini's statement today to a group of about 500 followers could be read simply as an appeal for unity, but it could also be seen as raising questions about how much political opposition his government would tolerate. It repeatedly stressed the need for national unity to rebuild the nation. He said:

"We cannot rule the country with one segment only, with one group only. The whole country must be integrated into the political system of governing. It is only through this mass integration of this population with the government and with the ruling class that we can govern our country."

The ayatollah spoke of the need to "reduce the last strongholds" of the shah's government and to deprive it of its last remaining resources. He also spoke of the need to punish the shah in a way that could be read either as a plea to let God take care of the former ruler and his followers in the afterlife, or as a foreshadowing of heavy reprisals against those who collaborated in his rule.

"Unfortunately," said Khomeini, "he has escaped the justice of our nation. We hope that very soon we will bring him back and try him and get back everything from him that he has taken away. However, the degree and intensity of his crime is such that it will be impossible for human beings to punish him for the crimes he has committed. How can we punish a man who has destroyed a whole pation? He has killed many people. How many times can we kill him, except just once? ...

"He will be punished in the hereafter for every crime that he has committed, for every soul that he has killed... He must be punished for every one of them."

The ayatollah approvingly repeated the example he has given before of a Jew who won a court case in medieval times against a powerful Islamic ruler.

"Even the non-Moslems will be protected," Khomeini said. "They have the right of raising their voice against the most powerful person of the country and bring him to justice."

Khomeini aides said last week that he had received a delegation from the Iranian Jewish community two months ago and gave them similar reassurances. Jewish organizational sources in France say the Jews of Iran have largely ignored appeals from Israel to flee the country.

Of the 75,000 to 80,000 Jews in Iran, only about 5,000 are said by Jewish sources in Paris to have emigrated since the start of the crisis a year ago.