Sunday (The Gospel According to Iso) is the sixth studio album by Australian vocal duo Vika and Linda Bull and was released on 11 September 2020.

[7] When the first COVID-19 pandemic lockdown began in Melbourne in March 2020, Vika and Linda Bull decided to sing one gospel song each Sunday morning for their followers on social media.

Music director Cameron Bruce played piano from his home in New South Wales and sent the files to Melbourne where the sisters added the vocals.

Vika added "Gospel music has been a huge influence on the way we sing; We love the rawness and minimal instrumentation of the early recordings of the great vocal powerhouses like Sister Rosetta Tharpe, Aretha Franklin and Mahalia Jackson.

[8] Jeff Jenkins from Stack Magazine said "You don't have to be a believer to dig these tunes" saying, "There's something special about siblings singing together and the sisters' voices beautifully complement each other.