The Alexandria Circuit Court jury in the trial of businessman Frederick Ramsay, who is accused of arranging the slaying of his partner, William B. Young, began deliberating yesterday after hearing two hours of impassioned closing arguments.

"Mr. Young was murdered to the benefit of Frederick Ramsay, at the direction of Frederick Ramsay and in the office of Frederick Ramsay," prosecutor S. Randolph Sengel told the jurors.

Ramsay, 41, is charged with first-degree murder and accused of hiring three men to kill Young, 54, the vice president of his Alexandria electrical contracting firm, in order to cash in a $150,000 life insurance policy, which had a double indemnity clause for accidental or sudden death. The company is now defunct.

Two of the three men allegedly hired by Ramsay testified against him during the trial. Ramsay did not take the stand.

Recapping what he called "compelling evidence" against Ramsay, Sengel said that despite testimony from three of Young's relatives that Ramsay had told them there was no insurance on Young's life, a brother of the defendant, who did not testify, called in the insurance claim within 24 hours of the slaying.

Defense attorney Louis Koutoulakos countered by calling the insurance policy "nothing but a red herring," and the key prosecution witnesses "unadulterated liars."

The witnesses who directly linked Ramsay to the slaying are Ralph Threatt, 44, who testified Monday that on Ramsay's instruction he bought the .22-caliber rifle later used to shoot Young, and Thomas Ebron, 26, who testified that he used the rifle to kill Young on Nov. 27, 1981, in return for $10,000 from Ramsay.

"Can you in good conscience find [Ramsay] guilty based on evidence from the mouths of these men?" Koutoulakos asked, adding that it would be impossible to convict Ramsay and "sleep the sleep of the innocent."

Although hiring someone to commit murder is a capital offense in Virginia, the prosecution is seeking a life sentence rather than the death penalty for Ramsay.

Threatt, who was charged with conspiracy to commit murder in the case, was granted immunity from prosecution after agreeing to cooperate with the government. Ebron, who pleaded guilty to first-degree murder, could be sentenced to up to life imprisonment. A third man, Charles Joseph, 36, also pleaded guilty to first-degree murder and could be sentenced to 46 years in prison.

Young was slain in his office at the Suburban Electric Co., 4114 Wheeler Ave., Alexandria.

The jury, which deliberated for one hour yesterday before recessing, is scheduled to resume deliberations today.