Michael Calvert has been found guilty of affray.
He will be remanded in custody until sentence on 19th December.
Michael Calvert was charged with a knife attack in the centre of St Helier.
This afternoon, the court heard both the prosecution and defence sum up the case and the jury decided after two hours that Mr Calvert was guilty of affray.
Before the jury went out, Deputy Bailiff, William Bailhache recapped the evidence for the jury members, informing them that they must believe "beyond reasonable doubt" that Mr Calvert committed the affray to find him guilty.
Victim, Alexander Ferguson, had his face cut by his attacker with a knife or screwdriver on April 18th, this year.
Advocate David Hopwood, prosecuting, said Michael Calvert was the assailant, but Mr Calvert denied the charge.
Yesterday, Advocate Hopwood said Michael Calvert had attacked Alex Ferguson on Bond Street at lunchtime on 18th April.
The jury watched CCTV footage showing Mr Calvert and three other men arguing in Hope Street before they disappeared out of view.
It then showed Mr Calvert walk back down with what appeared to be a knife and screwdriver in his hand.
Mr Calvert was arrested later and has admitted the charge of possession of a knife.
Mr Calvert himself appeared as a witness, along with Stuart Hutchison - a friend of Calvert's who was present at the attack.
Mr Calvert said another man, whom he knew, but did not want to name, came out of the town churchyard and was stood over Mr Ferguson at the time the attack happened.
Mr Calvert was arrested an hour or so after the incident and had already admitted the charge of possession of a knife.