Abdel Osman, his neck in a brace walks softly past the gurgling foutain in the quiet, tiled courtyard of Washington Islamic Center. He turns his neck with difficulty, his thin face wincing in the spring sunlight.

About 6,000 miles from the passions of the Middle East, where the Ayatollah Ruhollah Khomeini is calling for a holy war against the great American satan, Osman assistant director of the center, has to his surprise and the surprise of many other Moslems here fallen victim to that distant resurgence of Islamic militancy.

Osman was beaten to the ground a week ago in this very courtyard by two fellow Moslems who favor a purist approach to the faith. He is mute testimony to the fact that the backwaters of Islam are not immune to the tensions that have stirred Islam in the Middle East and Asia. Washington has about 50,000 Moslems.

In the last month the once-placid courtyard with its gurgling fountain has become the scene of heated debates, pamphletering, and even a few shoving matches between contending Moslem factions.

According to one prominent black American Muslim moderate, these factions, which include perhaps 50 people, are made up of militants who urge that strong stands against Zionism and American imperialism be taken by the mosque, some black American Muslims agitating for action against what they see as an antiblack and anti-Islam U.S. society, and foreign-born Moslems, including a number of Iranians and Egyptians, who argue for support of the Iranian revolution and other Middle East Islamic movements.

To those who favor maintaining the traditional tranquility of the center, the larlgest in the United States, the shift in tone is deeply distressing. They say that the actual number of militants and agitators is small and that most Moslems have little or no interest in encouraging the disruptions.

But if the militants are few, their presence has been felt, and some leaders of the black American Moslim community, who oppose the agitators, and many foreign-born Moslems with a more moderate view are clearly worried.

"There are people who want to take advantage of the situation," said Gen. Hassan Jeru-Ahmed, a prominent black American Muslim. "Islam is separate and apart from politics. They can't change that."

To many of the militiants, the central issue is that the center should take an active role in guiding American Moslems and others on how they should feel about the events shaping Islam in the Middle East and elsewhere. s

They contend that, because the center is financially supported by such conservative Arab countries as Saudi Arabia and Egypt, a country that has become somewhat of a pariah in the Islamic world, needed guidance is not being provided by men such as Osman and the center's director, Dr. Muhammad Abdul Rauf.

"Islam believes that important issues should be addressed in the mosque," said Bahram Nahidian, one of the most promient Iranians is Washington, who has been an outspoken supporter of the Iranian revolution and has talked regularly by phone with Iranian leaders and militants holding the American hostages.

"Many of our Moslem brothers have been killed around the world now," he said. "There is a saying in our faith: whoever wakes up in the morning and does not care about his fellow Moslems is not a Moslem. We must take stands [at the Islamic Center] and let people discuss the issues."

Nahidian does not dispute that assertion. "We want the center to tell the truth, even if they don't want to hear about Khomeini as a leader of the Muslims," he said. The prophet Mohammed -- the peace and blessings of Allah be upon him, the life of his companions -- what he did was a politcal action."

While the discontent with the center's leadership has been festering for a number of years, the dissidents say, two people close to the mosque say that the agitation has increased steadily since the Iranian students took American diplomats hostages in November.

The latest escalation of troubles took a sharp swing upward four weeks ago when the shah was permitted to enter Egypt, another said.

Jeru-Ahmed and others who align themselves with the leadership of Dr. Rauf clearly distrust the motives of Nahidian and leaders of the other factions. One moderate, who like many asked not to be identified, said that Nahidian and others are "clearly trying to use what you would call the pulpit for political action."

As an example of both the politicizing of the mosque and of the mosque's own openness to discussion, these moderates cite a confrontation three weeks ago between some militants and Dr. Rauf, who declined to be interviewed.

The miltants, demanded then that someone other than Dr. Rauf give the Khutab (sermon) at the regular worship service that Friday. According to Jeru-Ahmed, Dr. Rauf allowed Nahidian to do so out of his own "gooness and understanding" The militants say they were able to win that concession only after a vote of those present.

Later, about 25 to 35 of the 1,000 or so area Moslems who attended the service remained behind to demand changes that they would make the mosque more open to debate and the discussion of International and local issues, said one militant. Ten of them, including Nahidian, were elected by the group -- over Jeru Ahmed's objections that it was not a representative one -- to serve as a "temporary interin committee of the directors" of the center.

The militants say that, as a result, Dr. Rauf has not given the Khutbah since then. Instead, his place has been taken by members of the various factions.

On Friday, Dr. Rauf issued a statement intended to smooth the troubled waters at the center. He announced that a committee of the board of governors had been set up to look into complaints or suggestions from the mosque membership. The committee consists of the ambassadors of Tunisia, Bangladesh, Kuwait, Libya, Mali, and Pakistan.

Yet, while some of the Moslems who attend agree taht changes in the administration should be made, they are also disturbed by the disruptions that the militants have caused.

"Our ladies complain to us," said one Moslem from Pakistan. "They go for prayer and don't appreciate the shouting. Sometimes they are shouting the prayers. We hope it will change soon.