OAKLAND -- In the same monotone voice a Bingo caller might use to read numbers, Douglas Yim recounted to a jury this week how he shot his friend to death during a verbal argument about religion.

Yim, 33, sat emotionless on the witness stand as he described how he walked into his bedroom, grabbed his AR-15 assault rifle and then returned to the dining room and began firing bullets at Dzuy Dunh Phan, 25.

"I walked back toward the dining room, I saw him take a step toward me and he had a black object in his hand," Yim said in a steady, unemotional voice. "That is when I started firing at him."

Yim is accused of murder and attempted murder in the killing of Phan and the injury of another man in the early morning hours of April 2, 2011, inside his Herriott Avenue home in Oakland.

Yim said the killings were sparked by an argument he had with Phan about religion. The debate about the existence of God turned into a verbal assault that included derogatory name calling and, Yim said, Phan started talking about Yim's dead father.

It was an argument fueled by heavy alcohol drinking and the steady use of marijuana and cocaine, Yim said. It began as a little party, he said, but ended with death.

Yim said he became so angered at one point that he threw his cellphone into his flat screen television and then asked Phan to leave his house. Yim said Phan refused and then began to challenge him.

"He said, 'If you believe in God and God is so great then show me the wrath of God,'" Yim said. "He said something along the lines of I'm not leaving your home so go get your gun."

Yim's testimony comes as his lawyer, Mario Andrews, attempts to convince a jury that the killing of Phan should be manslaughter under the legal theory of imperfect self-defense. Andrews has said that his client didn't intend to kill Phan and shot at him with the mistaken belief that Phan had a gun.

But deputy district attorney Allyson Donovan told a jury that she will prove the killing was a murder and that Yim knew what he was doing when he fired six bullets into Phan.

Donovan questioned Yim about the shots fired and pointed out that Phan was hit six times all above his waist and with at least one shot in his head. Donovan also pointed out that Yim called his assault rifle a pistol when he first told the jury the story.

"You would agree the AR-15 is not a pistol, right?" Donovan said with a sarcastic chuckle as she held an assault rifle before the jury.

Donovan asked Yim why another witness said that Phan was trying to calm Yim down and questioned why police found equipment in Yim's house that would have allowed him to turn his AR-15 semi-automatic rifle into an M-16 automatic rifle.

Yim said the other witness was lying and said that he bought a conversion kit for his rifle because he wanted to protect himself.

"In the past, I had been threatened to be robbed," said Yim, who grew marijuana in his basement. "I wanted to protect myself."

Donovan also asked Yim why he just didn't call police if Phan was refusing to leave his house and Yim said that he didn't want police coming to his house because of the medical marijuana he was growing in his basement.

Yim will continue testifying Monday.