Haydar Haydar, 60, kept his head down while his three daughters comforted each other as the verdict was delivered in the NSW Supreme Court on Friday, almost two years to the day since Salwa Haydar, 45, was killed.

He had pleaded not guilty to murder but guilty to the manslaughter of the mother of his four children in her Bexley townhouse on March 30, 2015, claiming that he was substantially impaired at the time due to a depressive illness.

But Justice Peter Garling was not persuaded and found the "principal cause of the accused's conduct was his jealousy and anger".

"The attack was of great ferocity and persistence," Justice Garling said.

"His attack was predominantly caused by his jealousy and anger towards the deceased which had been building up in his mind for some weeks."

Justice Garling described Haydar as an "unreliable historian" and concluded that he had brought a knife to his wife's home and attacked her shortly after he had looked at her mobile phone.

The pair had a volatile relationship and had bought separate homes, although at the time of the murder Haydar was living at his wife's Bexley townhouse.

In the weeks before the murder, Haydar had discovered text messages sent by his wife, who worked as a drug and alcohol counsellor at St Vincent's Hospital, to a male colleague and he had incorrectly suspected the two were having an affair.

After a trip overseas to Lebanon, Haydar returned unexpectedly and, in a frantic and tense state, questioned two of his children about whether their mother had ever been unfaithful to him.

During the trip, Haydar had messaged his wife, telling her she had made a "grave" mistake and was living in a dream world.

In emotional testimony, Ola Haydar told the court that later that evening she heard a scream and she ran downstairs to see her mother backed in a corner and her father stabbing her in the back.

"I tried to get in the middle of it, to pull him away from her ... He didn't stop, he kept going," Ms Haydar told the court.

Ms Haydar, who was then an 18-year-old university student, was stabbed with the knife as she desperately tried to push her father away from her mother.

"[I was] saying 'What are you doing? Oh my god, you're going to kill her,' " Ms Haydar said.

Haydar later walked into a police station, with his hands covered in blood, and told the constable on duty: "My wife, I just stabbed my wife. I can't feel anything."

He told psychologists that he had no memory of what triggered the attack on his wife but claimed he had found the knife in her handbag.

Justice Garling also found Haydar guilty of causing grievous bodily harm to his daughter.

Haydar will face a sentencing hearing on May 5.