In a candid interview published this weekend, Oscar-winning actress Jennifer Hudson opened up about the brutal murder of three of her family members, and how her faith carried her through the terrible ordeal.

On 24 October 2008, while Hudson was touring, her former brother-in-law, William Balfour, killed her mother, brother and seven-year-old nephew in an 'act of vengeance' after his wife – Hudson's sister, Julia – left him.

Hudson later gave evidence at his trial, in which Balfour was convicted of triple murder and given three life sentences.

In an interview with the Observer, Hudson – who shot to fame first as an American Idol finalist in 2005, and later alongside Beyoncé in Dreamgirls which won her a best supporting actress Oscar – offered insight into the aftermath of the tragedy which shook her family, saying her belief in God helped her to keep going.

"I have definitely seen the highest of the highs and the lowest of the lows," she said. "You don't know how strong you are until you are placed in that kind of moment."

Having grown up singing in her church's gospel choir, Hudson insisted that her faith proved to be "the ultimate help" as she and Julia were forced to pick up the pieces.

"We always said: 'If He brings you to it, He will bring you through it,'" she told the Observer. "There would be no point in faith if it wasn't tested. My mother always told me no matter how negative your life seems to be, you must always look for a positive.

"That is what I believe a woman of faith should do."

In memory of her nephew, Hudson and her sister created what they call "Hatch Day", during which they donate supplies to local schools.

"She [Julia] looks forward to shopping for that, like she used to look forward to shopping for his birthday presents. My nephew was super into education – he used to call himself Dr King. She can pour his blessings on to these kids and keep his memory alive."

Hudson, who has criticised the focus on sex "and the same old things in music" in the past, also shared that she has always wanted to convey emotion in her songs, making them a "testimony" of her experiences.

"Certainly there is a lot of emotion there [in her vocals], but I think I have always been in that kind of space," she noted.

"What do they say in church? Sing from your heart, because you are singing to God. You know, when I used to sing those solos in church I would go through every line and ask the director: 'What does this mean? What are we trying to convey here?'

"If you can't feel the emotion of a song, how do you expect anyone else to? It's like a testimony in that way," she added.

"The world is a broad place. Even on my first album I was like, 'Isn't there more to sing about in the world? Or to talk about? There is so much more out there to portray...'"