In the darkened hall of the Sheraton Washington Hotel, only the candlelight flickered as the Rev. Jerry Moore prayed over the "exchange of ideas." That was a polite description of the war of words that marked this week's National Urban League convention.

But as the League closed four days of back-to-back speeches by Reagan Republicans, the consensus was that no one on either side had successfully illuminated a way out of the conservative-civil rights impasse.

"We are not going home reassured," said Vernon Jordan, the League's president, as he sped down the hall to the last reception and dinner. Since Jordan had sounded the battle cry Sunday, Vice President George Bush and six Cabinet officers, as well as some old allies such as former vice president Walter Mondale, had taken the League's podium.

Stepping down from the dais, Melvin Bradley, a senior Reagan policy adviser and the highest ranking black in the White House, assessed the convention. "I don't think we can make a determination of a new directior this early. But Bush and [budget director David] Stockman gave them food for thought. But I haven't heard any feedback on new ideas."

Though overfed with speeches, the 3,000 people at the dinner sat down for steak and more words. "We have lost some initial battles in our struggle to meet this across-the-board challenge to the quality of life for all of our people. But the war goes on," said Del. Walter Fauntroy (D-D.C.). "Why should we take $1.5 billion from the free-lunch program and not take $3 billion from the lunch program we have for the rich. We have a 'free lunch' for the rich, you know. It's called the 'three-martini lunch' tax expenditure. We don't want to take all the free lunch programs. Just give us half of it, $1.5 billion, and we can restore the child nutrition programs in our schools."

In the corridors of the convention, evaluations of the Republicans' interaction with the League members ranged from effusive to wary. "I thought people were very receptive, especially to George Bush. Secretary [of Education Terrel] Bell said he felt right at home and went on for an extra 45 minutes," said Armstrong Williams, a congressional liaison with the Department of Agriculture and, at 21, one of the administration's youngest appointees. Williams, like many others reviewing the convention, had felt uneasy at Labor Secretary Raymond Donovan's reminiscing about the times he was "poor and used to shine shoes." Said Williams, "People were insulted, and I don't think it was in good taste."

In the last of the verbal sparrings Fauntroy, the evening's speaker, packed in a long list of practical suggestions, two mobilizing songs and some homespun slogans. He was cheered when he suggested that the League members break down their local membership list to target congressmen unresponsive to social needs.

But he stirred up the crowd with his last entry into the word war. "Fire can't burn us, water can't drown us. Have you that something?" said Fauntroy. The audience yelled back "yes." Then Fauntroy said, "Let the world know that something is in you."