It could have gone either way, Marion Barry told his television audience last night, fight or quit.

His son, Christopher, who will turn 10 on Sunday, was for fighting.

"Daddy, you've got to run. You've got a lot of courage," the mayor quoted his son.

Christopher's parents were less sure.

"We've had our times with it, vacillated back and forth," the mayor said. "I talked to Effi about it. She's saying, 'Let's go for it again.' Then she says, 'This abuse has been too difficult for me and Christopher.' She said, 'If that's your decision, I support it.' "

The mayor's mother, he went on, has always thought it "a miracle that I ever became mayor."

The final decision, the mayor made clear, was his. "This is not a ploy. This is too difficult. I had to go far down for this decision. I agonized about it. I cried about it. I prayed about it."

And he made clear that the old Marion Barry -- the pre-arrest, pre-treatment, pre-trial Marion Barry -- would have chosen differently.

"I have come back with a certain calmness and a certain humbleness and a certain sensitivity. My ego is gone now," he said. "There was a time when my ego would have been so big that I would have said, 'I don't care if I go down and don't get but five votes . . . . The ego has to move aside."

The ego was moved aside but not lost last night in the mayor's announcement on Howard University television that he would not seek a fourth term, and in his interview immediately following with Kojo Nnamdi, host of "The Evening Exchange." In the hour on camera he was quiet but resolved, subdued but proud, professing to be understanding of both his critics and his supporters.

His intent, the mayor said, was to speak to his supporters, to all the people, "intimately and close up."

The mayor made clear that he was not leaving beaten, or frightened by his legal troubles, or too sick to go on.

"This is not a eulogy . . . . A lame duck does not mean a dead duck. We're not dead."

And he said this: "I'm not a sick person and unable to do the job. I'm mentally capable to do it. I'm physically capable to do it. I'm spiritually capable to do it. I just don't want to do it another four years."

Barry said he knew that some viewers would cheer his departure.

"They can cheer, but on the other hand, when the cheering is over we've got to live in this city . . . . Those who want to cheer, I can't stop them."

He concentrated instead on his supporters.

"I know for a number of you this is as emotional an announcement as it is for me. Many of you are saddened. Many are disappointed, hurt, and probably some of you are very angry. On the other hand, many of you have been supporters over the years, also feel relieved.

"I too share all these feelings, but I also feel joy and gratitude. Because you allowed me to serve you for over 30 years."

Finding another job, Barry said, is "the least of my concerns. I was born with nothing, born on a farm in Mississippi . . . . I'm not hung up on money."

He rejected the idea of a typical business career.

"I doubt if I ever will be just a straight business people, pinstripe suit, with a sports car and just off the golf course and the tennis court and off the islands and that's it."

Perhaps some sort of work speaking out for recovering addicts would be right, he said, but there would be time later for that decision, after the trial.

"I'm proud to say to you tonight with the grace of God, and a good treatment program, today is my 145th day clean of any chemicals. For some, that's a short time. For those of us in the recovery community, it's a long time. I continue to try to keep this achievement -- one day at a time . . . .

"I have succumbed to a disease that affects millions of Americans but which is misunderstood by far more. We've just begun to treat dependence on alcohol and on mood-altering chemicals as an illness. And some still think that it's not such.

"Some think it's just a matter of exercising pure will. They do not know that instead it requires the mind and the body coming together with the spirit to find joy and happiness."

Barry also spoke of having a renewed faith in God, fueled by his time out of the city at drug treatment facilities after his arrest in January.

"I've come back to Washington a more complete person, a more content person, a more sensitive person and a more humble person. I've had a spiritual awakening, and thus I've renewed my contact with a higher power I know is God.

"I've come to realize that I cannot neglect the spiritual side of my life -- that as I take one day at a time, I must take it with God as my guide."

Barry made a point of defending his intelligence and his resolve. "God gave me a good brain, and sometimes that's missed in this discussion. He gave me tenacity. He gave me a commitment to spend most of my time working for people."

Time after time he returned to the theme of resolve. He was leaving but not quitting. "I'm not one to lay down. The question is can you get up."

The mayor didn't seem bothered when one caller to the show told him, "Take your high murder rate with you."

The host, Nnamdi, quickly cut off the caller.

That call was followed by a 72-year-old woman who thanked Barry for his work on behalf of older people.

The 54-year-old mayor seemed taken aback when Nnamdi asked how he wanted to be remembered. He repeated that it was no time for a eulogy, and said he was "certainly one who's had compassion for the least among us . . . .

"I don't regret anything. The good times or the bad times, we've had some of that. The ups and the downs, we've had that. It's hard to think about yourself, because you think about that you're thinking about death or a eulogy. But the Barry legacy is here."

When asked for a last word, Barry said, "First of all, pray for me. And secondly, have faith. It's gonna be all right."