A jury of nine women and three men deliberated for three hours and then recessed for the night after the nine-day trial of Rep. Charles C. Diggs Jr., (D-Mich.) came to an emotional conclusion yesterday. Deliberations by the sequestered jury were to resume today.

Diggs, who had sat impassively for most of the trial, was sobbing at the end of defense lawyer David Povich's summation to the jury.

Moments later, Diggs' earlier testimony in his own behalf was attacked by Justice Department prosecutor John T. Kotelly as being "ludicros," "ridiculous," "unbelievable" and "incredible." Kotelly told the jury in his final argument that Diggs' testimony "doesn't square with life, doesn't square with the facts and doesn't square with reality."

Diggs is charged in a 23-count indictment with mail fraud and illegally diverting more than $60,000 in his congressional employes' salaries to buy his personal and congressional bills.

Defense lawyer David Povich argued before the jury that the prosecution's principal witness against Diggs, his former congressional office manager Jean G. Stultz, had misrepresented to the jury her motivation in agreeing to pay Diggs' personal bills from her salary.

Povich told the jury that "there is a very great difference between what she did at the time" - from October 1973 until in 1976 - and "what she testified to now." Stultz, Povich asserted," attempted to fabricate what her feelings were at the time."

Povich disputed Stultz's testimony that she agreed to buy Diggs' personal bills from her salary only because she considered it virtually "a condition of employment."

Recalling for the jury the polse and precision that characterized Stultz's testimony, Povich told the jury, "she's not a weak individual. She's a very strong individual. She did what she wanted to do." It was Stultz, not Diggs, who "decided when she was going to give him money and when she was not," Povich said.

Povich attacked Kotelly and the government's presentation of the evidence, which, Povich said had been "carefully formed so as not to bring out the entire truth." As one example, Povich suggested that the government had been less than candid when discussing whether or not Stultz had been granted immunity from prosecution, which she was.

"There really is something unholy in all of this," Povich said."Why must they press so hard?"

"We are talking about the measure of a man in this courtroom," Povich said. "We have brought you people who can help you decide that question." Referring to the appearance as character witnesses on Diggs' behalf of Coretta Scott King. United Nations Ambassador Andrew Young, Detroit Mayor Coleman Young and civil rights leader Jesse Jackson, Povich said, "History was made in this courtroom that day on this man's behalf."

Diggs, the senior black congressman with 24 years of service, had listened to the testimony impassively throughout the trial. But he was sobbing at the end of Povich's summation.

Kotelly, rebutting Povich's argument, asked the jury to consider why it was necessary for Stultz to have immunity in the first place. "Who put her in this position?" he asked. "It was the congressman who put her in this position." Kotelly insisted that Stultz had not helped Diggs voluntarily. "Is it anything terrible or wrong that the government agreed not to prosecute Jean Stultz?" he asked, his voice rising. "Who got the benefit?I would submit that that is the man who got the benefit," he said, pointing at Diggs, "not Jean Stultz."

Referring to Povich's description of Diggs' integrity, Kotelly asked, "what kind of integrity does a man have who's living off his employe's salary?"