Theodore Gregory, a 29-year-old Middleburg horse trainer, convicted last night in Loudoun County Circuit Court of attempting to murder his estranged wife Monique when he discovered her in bed with one of his best friends last August.

The jury of nine men and three women deliberated 4 1/2 hours before returning its verdict with the recommendation that Gregory be sentenced to seven years for attempted second-degree murder and one year for using a firearm during that attempt, which resulted in the death of Howard LaBove, a fellow horse trainer.

The jury acquitted Gregory of the more serious felony of breaking and entering with intent to commit murder while armed with a deadly weapon. Conviction on that charge would have carried a minimum 20-year sentence.

"I don't feel to bad at all," said Blair Howard, one of Gregory's four defense attorneys. "He [Commonwealth's Attorney Thomas D. Horne] was asking for his life."

No date was set for formal sentencing; Gregory is jailed without bond. The prosecutor has indicated he also wants to try Gregory for LaBove's murder, a move that hitherto has been blocked by legal complications resulting from the fact that the principal witness to the slaying is Gregory's wife.

The verdicts were returned after a four-day trial that had all the ingredients of an X-rated soap opera.

In his closing arguments to the jury yesterday, another of the defense lawyers, a 79-year-old bowlegged legend in Northern Virginia courtrooms, had rolled all the sex, violence and drama of the trial into one fire and brimstone sermon on the Middleburg love triangle trial.

"I hope there are some people on this jury who recognize there is such a thing in this country as morals," said T. Brooke Howard, who argued that Gregory could not stop himself from shooting last August when he found his estranged wife in bed with a man he considered one of his best friends.

"Call me an odd fellow and an old-timer, but I don't approve of a woman who's got a husband going out and laying up with another man," said Howard who alternately crouched, knelt and raised his hands to heaven during a performance that many in the Leesburg courthouse had awaited all week.

Gregory's trial stemmed from the late-night shooting Aug. 20 that left LaBove dead from three .45-caliber pistol wounds. Gregory's estranged wife Monique, whom he discovered in bed with LaBove, escaped from her lover's cottage, a few miles outside of Middleburg, and fled naked across a farm field to a nearby tenant house. She required 300 stitches to close cuts suffered as she plunged both arms through the window of a locked back door of the tenant house.

The jury hearing the case -- one of the most celebrated in county history -- was asked to decide only whether Gregory was guilty of the three felonies involving his wife.

A charge of murdering LaBove was dropped, prosecutors said, because under Virginia law spouses may not testify against each other in crimes that are alleged to have been committed against third parties. Gregory's convictions last night make it eaiser for Monique Gregory to get a divorce that would clear the way for her to testify at a murder trial.

Before the trial began Judge Carleton Penn admonished prospective jurors to disregard what he termed the "unwritten law" -- that a jealous husband has a right to violence if he finds his wife commmiting adultery.

For much of the four-day trial it seemed that both the prosecution and defense were directing their questions to both the facts of the shooting and the morality of the three principal characters, all well known in Middleburg's horse society.

"The fact that [Monique Gregory] engaged in sexual intercourse with another man while she was still technically married, that's a problem," conceded Loudoun prosecutor Horne in his final arguments. "But we don't want to intertwine morality with murder."

"Gregory's main defense was innocent by reason of temporary insanity as a result of "irressistible impluse." Under Virginia law a person may be innocent of an offense by reason of irresistible impluse if by "mental illness or defect" that person is "deprived of the willpower" to resist an act.

Judge Penn warned the jury yesterday that mental stress and mental illness were not to be confused. "Frenzy growing out of passion and jealousy, no matter how furious, is not insanity.

The defense produced a psychologist and a psychiatrist who testified that Gregory was suffering from severe depression and a schizoid personality disorder. Friends called to the witness stand to corroborate that diagnosis described Gregory as emotionally devastated, extremely withdrawn and obsessed with the idea of getting his wife back. One witness said Gregory even talked on one occasion of kidnapping Monique and taking her to some mountaintop.

The prosecution called three of its own psychiatrists who testified that Gregory was not suffering from a mental illness. One of those psychiatrists, Dr. James Dimitris, testified that the sequence of events related to him by Gregory on the night of the shooting indicated that it was a premeditated act.

"I submit to you that Ted Gregory is not the poor, distraught, crushed man that the defense wants you to believe," said prosecutor Horne. "He is a cold-blooded killer."

In the closing arguments the defense accused Monique Gregory of lying about the details of the shooting because of her hatred for her estranged husband who she said had assualted her on three occasions since their May separation.

"I tell you, she put it together to suit her purposes," said attorney T. Brooke Howard, whose son, 38-year-old Blair Howard conducted most of the defense for Gregory.

Throughout the trial, the courtroom was frequented by Lessburg lawyers who said they hoped to T. Brooke perform. The elder Howard, who has the leathered face and gruff manner of a potato farmer, is well known in the legal community for his courtroom theatrics and his success.

Ten years ago Howard successfully used irresistable impulse as a defense for a Northern Virginia car salesman who abducted a 30-year-old Alexandria woman, held her for nine hours and raped her.

But Howard also has had losses. In1961 he attempted to convince a jury that a bank robber was "psychoneurotic." His client, said Howard committed crimes in the hope of getting caught because for him jail was a "mother fixture." His client was sentenced to 45 years in prison.

Yesterday after the jury retired to deliberate, some of the spectators who had faithfully attended the trial stood outside the courthouse and discussed the case. "You know what I figured the moral of this whole thing is," said one man. "Don't cat around in horse country."