The incident took place in a basement in Hälleforsnäs in October.
The victim suffered serious injuries to internal parts of the stomach and was taken to hospital by ambulance.
There, the victim was close to death.
The man in his 40s states that he had no intention of harming his friend, but was sentenced on Monday at the Nyköping district court.
The man was sentenced at the same time for assaulting the same friend, which happened two months earlier.
He must also pay nearly SEK 270,000 in damages.