The shocking incident happened in the course of a violent row on Windmill Road in Crumlin at around 5.30pm on Tuesday and sparked a major garda operation.
The 26-year-old victim was stabbed and beaten in the incident by a 24-year-old local man with connections to the Captain's Avenue area of Crumlin.
It is understood that the victim, who is from the south inner city but now living in Ballyfermot, has only recently been released from prison.
Sources believe that the origin of the bitter dispute was a row over a woman, and the vicious assault happened on a footpath.
Detectives were alerted to the attack but the victim refused to co-operate with gardai and also refused to get hospital treatment.
Because of this, it is hugely unlikely that there will be charges in the case.
Officers then received information that the victim was planning to "gather together a gang of heavies from the Cabra area" to avenge the stabbing.
"Tensions were very high on Tuesday night -- a special policing plan had to be put in place straight away," said a source.
Armed gardai flocked to the area and kept up an "overt presence" during the course of the night.
A source explained: "The night passed off without incident because of the presence of the armed units.
"But this is not the end of this -- there are some serious players involved and gardai are on alert.
"It could even be the start of a new feud in the Crumlin area."