Two months ago, Saul Arana, 29, was trying to hold down a part-time job as a housewares clerk in the Peoples Drug store on F Street NW. But the war in his Nicaraguan homeland was growing, he was marching and protesting here at every opportunity, and there just were not enough hours in the day.

"The manager said why don't you take some time off and then you can come back," Arana reminisced with a smile.

Arana will not be going back to Peoples. A week ago, he was appointed charge d'affaires from the new Sandinista-backed Nicaraguan government to the United States.

In the world of lost causes usually swirling around 18th Street and Columbia Road -- where refugees from both right- and left-wing dictatorships seem to be forever futilely pasting protest posters on walls -- Arana is a new and rarely found hero.

Since he came here in 1973, he has been one of the most prominent leaders in Adams-Morgan's ever-boiling political melting pot. Like so many others in the neighborhood, the jobs at which he made money -- at Peoples or teaching math at the University of the District of Columbia -- never were his real vocation. His business was fomenting social change and supporting the revolution that might someday take him home.

If there was a protest March -- for tenant's rights, against a new immigration law, against any of the world's oppressive right-wing regimes -- Arana would be there.. If the demonstration was against Nicaragua's Somoza dynasty, Arana could be seen leading the chanting support of the Sandinistas, his tall bulky frame towering above his companions.

Only two weeks ago, he was arrested after an attempted takeover of the chancery he now legally controls.

Arana was almost as much a fixture on the protest and picket scene as his predecessor, Guillermo Sevilla-Sacasa, was on embassy row's champagne and caviar circuit.

But now Arana is inside the embassy offices, not marching in front of them, and the transition has not been completely comfortable. "I know I have to attend meetings," he said Tuesday, looking slightly chagrined. "But . . . I like to be carrying a sign."

"I don't want to change my personality," Arana said, glancing out through the chancery doors. I want to be involved with what I've been in the past."

He still wears his hair long, still dresses in open shirts and casual slacks -- when he can. "You have to dress properly when you go to the meetings. I sometimes wear the clothing of my friends."

Arana drives his old Buick instead of the embassy limousine and lives with his wife and 4-year-old daughter in an apartment off Columbia Road rather than in the palatial embassy residence. "I love to live in a barrio," he said, laughing easily. "I don't have to drive in from Maryland."

Uninhibitedly contrasting himself with his protocol-obsessed predecessor, Arana said that if there is ever enough time, "propably someday you're going to see me painting the embassy, fixing a lamp or whatever is needed."

His friends see a certain revolutionary logic in all this, and it fits the Arana they've always known.

"He's a real grassroots person," said Maria Elena Orrego, who remembers Arana from the days when he was organizing the Fields of "plenty food cooperative on 18th Street NW. "Saul is a very simple, very reachable person. He was outspoken, but he made lots of friends. He never assumed the 'role' of a leader, although he was."

Attorney Michael Maggio first met Arana cutting cheese at Fields of Plenty, Maggio later helped Arana get his immigration papers and now handles legal affairs for the embassy.

"It's so good to be on the swinning side for a change," Maggio said. "Saul represents the aspirations of so many people in this community -- the Paraguayans, the Salvadorans, the Chileans. Washington's a city of exiles. There are exiles all over the place. What's unique about Saul is he integrated himself into the struggles of the people of this city."

It was because of his ability to work with virtually anyone that Arana was able to make the Nicaraguan revolution one of the few issues that has ever seemed to unite the disparate political elements of Adams-Morgan.

As head of the Washington Area Nicaragua Solidarity Orginization, Arana gathered as many as 1,000 people for protest against Somoza. He forged intimate links between Washington's radicals and Nicaragua's revolution.

But he paid a price as well. He has been a student activist in Managua before he went into exile in 1972 in Chile, only to flee again when the Marxist regime there was toppled in a brutal military coup.

Enoc Ortez, one of the close friends who accompanied him to Washington in 1973 and worked with him here, retunred to Nicaragua earlier this year to fight with the Sandinistas and was killed two weeks before Somoza resigned.

Arana's father was fired from the government clerk's job he held for 20 years after he accompanied his son to a Sandinista's funeral in the early 1970s. Two months ago, the elder Arana, was murdered in his Managua home -- stabbed one morning when everyone else was out of the house.

"He never was involved with politics," Arana said, having difficulty talking about the incident. "We don't know who did it. I can't make clear to myself how it happened -- whether it was (the Somoza government's) revenge for my activities in the United States, or robbery. A briefcase and some papers were stolen."

But Arana said he has no interest or time to think about personal problems about which little now can be done. His nation is bankrupt and devastated by war. Nicaragua is in the midst of overcoming extremely sensitive problems in its relations with the United States, and Arana, at least for now, is near the center of the action.

He also has his future to contemplate. Eventually a full ambassador will be appointed, and after that Arana is not sure what he will do. He would like to return to Nicaragua, but he said his government may want him to stay here or go to another embassy.

There is the problem of finances, too. Arana is not being paid for his new duties. "There is no money," he said.

"I hope that if I have the time I will continue to teach in the Latino program at U.D.C.," Arana said, smiling. "I love to be a professor. This summer was only my second semester.I hope that in September I get again my job."

But peoples, Arana said, has seen the last of him. CAPTION: Picture 1, Saul Arana, Nicaragua's new charge d'affaires here, recently quit a drugstore job. By Margaret Thomas -- The Washington Post; Picture 2, A local melting pot leader, Saul Arana stands before the embassy where he works. By Joe Heiberger -- The Washington Post