CCTV video captured the moment a knife-wielding attacker paid a visit to a neighbour he wrongly believed had set fire to his home.
Vincent Southecoat, 38, was spared jail after being filmed holding a 12-inch blade to the throat of Mr Henley, 50, on Hull's Bransholme estate.
In an attack described by a judge as "outrageous and dangerous", Southecoat knocked on Mr Henley's door in a drunken rage and left his victim with stab wounds on his elbow and hands.
Mr Henley's partner helped him close the door and call the police - but crazed stabbed at the door with the knife before shouting "I'm going to come back and kill you".
He even turned on neighbour Brian Williamson who had come over to view the incident – biting him on the ear and striking him over the head.
The father -of-four avoided jail after Hull Crown Court heard he had already spent four months in custody on remand - around the time he would have served on an eight-month sentence.
Judge Thorn QC said: "Certainly, sentencing practice requests that people who use knives in public places receive custody, because there have been so many unfortunate stabbings and because those who wield knives cannot be quite sure how much medical intervention can be used to save someone's life.
"But I am taking a wholly exceptional course. You have already served an eight-month sentence and I would have passed a 20 month sentence. I have to set a balance. You have responsibility for these four young children, you have a job and you are spoken well of in the community."
Southecoat, of Blandford Close, Bransholme, told police he thought Mr Henley had set fire to his house - but no records of an arson attack on his home could be found.
He admitted wounding, assault occasioning actual bodily harm and possessing a knife in a public place after the incident on June 13 this year.
Southecoat was given a 12-month sentence, suspended for two years, a two year supervision order and 200 hours of unpaid work in the community.