The Christmas spirit became manifest for Keith Blum and Allen Tremont yesterday because one had a dead battery and the other had a set of jumper cables.

Blum was driving up Massachusetts Avenue past Union Station when he saw Tremont standing in the rain next to his 1974 Plymouth with the hood up. Blum said he knew right away what the problem was.

"My first instinct was to just keep going," he said. "But then I thought how I would feel. A dead battery is bad enough, but on Christmas Eve . . . awful."

So he pulled over to give this stranger a hand.

"I'd been waiting 15 minutes and I was hoping a police car might show up," Tremont said. "You really don't expect people to stop in this weather. I hate to admit it, but I probably wouldn't."

The jump took no time at all. When his car was running again, Tremont said to Blum, "I guess this is the Christmas spirit, huh?"

Blum laughed. "You have a merry Christmas," he said. "I'll just go home and feel like a real good samaritan."

"Merry Christmas to you," Tremont said.

The Rev. Elizabeth P. Wiesner told a crowd of about 1,500 worshipers at the National Cathedral yesterday that God's plan in sending Jesus to earth was to release mankind from bondage. But "the birth of the Messiah depended on the act of assent of a 15-year-old Jewish maiden," she said.

Wiesner told her listeners that they, too, might expect to hear from God. "But let me assure you that it's extremely unlikely that you'll ever look up from an everyday task . . . and see the Angel Gabriel. Annunciations rarely come to us in the 20th Century in a simple form."

God "will try again, he will try to speak to us again," said Wiesner, "perhaps in the form of an uninvited, unwelcome guest at the dinner table . . . perhaps in the form of an inconvenient telephone call during a Redskins game."

Mark MacDonald, 8, Lawrence MacDonald, 11, of Bethesda agreed that yesterday's special service was "great," but they sneaked out during the musical segment to wander through the gift shop and catacombs.

Despite all their parents' efforts at concealment, both MacDonalds confidently predicted what they would be getting for Christmas today-miniature railroad pieces for Lawrence, according to Lawrence, and a new wagon for Mark, according to Mark.

The Sunday regulars and some special celebrants at the Hawk and Dove, a bar on Pennsylvania Avenue, spent the day in quiet but expert celebration.

New York's junior senator, Daniel (PAT) Moynihan, was working on his second Guinness, in the company of his 22-year-old son Timothy and his brother Michael, who were nursing their own beers.

"Cheers," said the senator, lifting his mug slightly. "We are here having a Christmas Eve drink, a glass of beer and some cheeseburgers . . . "

"And I thought you were taking us out for champagne and oysters," Michael Moynihan, a public relations consultant, objected jokingly.

The 7-Eleven store at 7461 Lee Hwy. was doing a brisk business yesterday morning and Dave Fleming was jumping from one side of the counter to the other to keep up.

"I don't mind working today," he said. "In fact I'm going to work tonight on security and work tomorrow too."

"I get paid the same," he said. "A lot of 7-Elevens are closed tomorrow but I want this one open. I just want to help the people in this neighborhood if I can. Staying open can help them if they forget something or whatever. So I'm glad to work."

"You think we're crazy?" asked Piero Sarti, as he stood with his girlfriend in yesterday afternoon's downpour and gazed respectfully at the National Christmas Tree on the Ellipse.

"We just came to see it. It's a good remembrance," said his friend, Sandra Teran. Their Christmas shopping was done and they hadn't wanted to waste time watching football, they said.

"It's really a pretty nice picture," said Sarti, an engineer, as he fumbled with his Minolta camera. The nation's Christmas tree obliged by suddenly lighting up.

The first challenge that customers faced at the Toys-R-Us store in Silver Hill was safely weaving through the parking lot to a parking space. The second was making their way through the hordes of last-minute shoppers.

"The last two days we've opened at 9:30 and by 9 o'clock there have been people standing outside waiting to get in," said Debbie Jackson, who answered the phone yesterday by saying, "Toys-R-Us, we're open until 8."

"We keep trying to put new toys on the shelves as they get bought but we can't keep up. It's satisfying to get a lot done, but it's also very busy."

Not all the toy customers were awash with Christmas spirit, however. A middle-aged woman became upset when Tim Yankowski stepped in front of her carrying two large boxes without realizing she was in the cashier's line.

"Hey," she yelled. "What do you think you're doing?"

"Oh. I'm didn't realize you were in line," Yankowski answered politely.

"Like hell you didn't," said the woman, who refused to give her name.

"Merry Christmas," Yankowski said, shaking his head.

Ten-year old Sharon Jackson spent the better part of her Christmas Eve morning nervously awaiting the moment when minister Elwood John McClem would gently dunk her in the baptismal waters at Washington's Bible Way Church so that, as she explained softly later, she could "receive the Lord as my savior."

"I feel O.K., but my nose is stopped up. it's just swimming in a pool backwards," said Jackson, a Meyer Elementary School fifth-grader, as she waded out of the shallow pool at 1130 New Jersey Ave. NW. A church member, Lorraine Easter, quickly wrapped a towel around her drenched white pinafore while the Sunday congregation of about 250 crupted in a chorus of "Jesus Saves."

The baptismal decision, she said later, had been made about a week ago, but only revealed to her parents, Agness and Joseph Jackson, before breakfast yesterday. Her best friend, Tracy Marshall, had been baptized recently, but she said that had nothing to do with her decision.

"I just thought it was time," she said simply.

His wife is in Kentucky and his two grown sons live in Arkansas, but William Lewis was getting ready to drive a bus to Clarksburg, W. Va. on Christmas Eve.

"I've been working Christmas Eve and Christmas Day for 22 years now," he said yesterday in the Greyhound bus station. "I'm used to not being with my family by now."

Still Lewis admitted he wished it could be otherwise."Maybe someday I'll have enough seniority to get off on the holidays," he said with a laugh. "I do start to feel sort of lonely when I'm going down the road and I look around me and see Christmas lights and decorations on the different houses. I start wishing I was inside my house with my family sitting by the Christmas tree, instead of driving a bus."

Christmas Eve for Lewis was a six-hour drive to Clarksburg. He was scheduled to arrive at about 10 p.m. "I'll have to go home, get some sleep and then drive back here at 8:45 a.m. tomorrow," he said. "Basically, Christmas will be just another working day. Too bad."

They sat huddled in groups of two and three, trying to dry off from the steady rain outside. Whether the government likes it or not, the National Visitor Center at Union Station is still one place where street people go to escape the elements.

"I spent last night here and at the Post Office," Viola Tennant said. "When they kicked me out of here, I went over there. When I got kicked out of there, I came back here."

Yesterday afternoon, Tennant was trying to reach her daughter to see if she could spend Christmas Eve with her. "I haven't reached her yet but I'm still hoping," she said, "I think maybe her number was changed, I don't know. If I can't find her I don't know where I'll spend the night. I'll just have to figure something out."

Did she feel in the Christmas spirit at all? "Course I do," she said. "Look, I can't compalin. I don't have a place to sleep, I don't have anything to eat, but I'm alive. I've lived 57 years. That ain't too bad. I'd just like to live a few more."

Tennant got up from her seat and walked towards the restroom. "Got to go in there for a while," she said. "If you stay in one place too long the police come and make you leave."

The Park Police at the front of the Visitor Center advised a questioner to call headquarters when asked if they were allowing people to remain inside during the rain.

"We're letting them stay inside and dry off for an hour or so," the supervisor said. "As long as they don't bother anybody."

"They put you right in the Christmas spirit," Tennant said as she moved to a new location. "They say 'Merry Christmas,' while they kick you out the door."

. . . he stood with his girlfriend in yesterday's downpour and gazed respectfully at the National Christmas tree . . .