Thomas Telford, 21, had denied assaulting colleague Campbell Thomas to the extent that he lost a kidney after being stabbed eight times.
But a jury at the High Court in Livingston took less than 90 minutes yesterday to return a majority verdict finding him guilty and he was remanded.
The jury also unanimously found Telford guilty of assaulting his victim’s neighbour, Lillian Hood, who has since died, by seizing her by the throat during the same incident.
And they convicted him of attempting to defeat the ends of justice by disposing of the weapon, a red-handled kitchen knife with a 10-inch blade.
At the time of the attack, Telford, of Castlemilk, Glasgow, was on bail for substantially similar charges of threatening or abusive behaviour and police assault.
The court heard how the pair had been out drinking around five pints, followed by Buckfast and vodka.
Mr Thomas, 19, told how he lost a kidney and was scarred for life after Telford stabbed him on August 12, 2016 in Lurie Place following a drinking session in Edinburgh after finishing work.
He told the jury: “I fell to the ground. I stood up and tried to get away. I tried to dive over my couch to get to the kitchen, bleeding from my lower stomach. As I went over the couch I was getting stabbed in my back by Thomas.”
PC Sophie Lesley, who went to Telford’s home afterwards, said he told her: “I stabbed him. I’ve left him for dead.”
Judge Lord Uist told Telford: “You’re bound to receive a lengthy sentence for these crimes.”