Earlier in the trial the court was shown a videotaped interview between Khairi and police which was made shortly after he called 911 in 2008 to report his wife was dead.
"I can't talk anything. I am not normal. My brain is not working," Peer Khairi told the police hours after he admitted to stabbing his wife and slit her throat so deeply she was nearly decapitated.
Today, when he took the stand in his own defence, Khairi spoke through a translator.
He emphasized he's had psychological issues for years and admitted he has attempted suicide at least six times.
Khairi, 65, is accused of second-degree murder in the death of his wife Randjida Khairi.
The Crown has argued Khairi was enraged with his wife and children because they dressed differently and were disobedient, disrespecting his version of a Muslim family.
But Khairi told the court he had a great relationship with his six children. "I never said anything to upset them," he testified.
Khairi admits his relationship with his wife deteriorated when they moved to Canada because he couldn't find work to support his family.
He said she was always swearing and yelling at him, especially on the day he killed her.
She called him a coward.
"She told me I was honourless that [I] don't work," he said.
In a twist Khairi told the court he killed his wife in self-defence.
He said Randjida "grabbed a small knife and came towards me."
"I wasn't well and I was scared. I was feeling scared. I had no choice." he added "I grabbed her knife otherwise she would have stabbed me."
With his other hand, he says he grabbed her throat, put her on the bed, stabbed her in the abdomen twice, then grabbed another knife and "put it to to her throat with no pressure added."
The trial continues.