Unhappy couple: He accused the Lethal Weapon star of saying particularly nasty things about his ex Oksana Grigorieva
In an explosive nine page letter Joe Eszterhas also claims the actor told him he was happy when John Lennon was shot, and accused the Beatle of having a messiah complex.
He made the claims after his script for The Maccabees, which tells the story of the Jewish warrior who defeated the Greek-Syrian armies in the second century B.C, was rejected by studio Warner Bros, putting the project in limbo
It reignites the row about whether Gibson, 56, is an anti-Semite, which was sparked when he was made a slew of slurs in 2006 after he was arrested for suspicion of drunk driving.
The row started when website TheWrap got a hold of Eszterhas' letter, in which he says: 'I’ve come to the conclusion that the reason you won’t make The Maccabees is the ugliest possible one. You hate Jews.
'You continually called Jews "Hebes" and "oven-dodgers" and "Jewboys."
'You said most "gatekeepers" of American companies were "Hebes" who "controlled their bosses."
'You said the Holocaust was "mostly a lot of horses**'." You said the Torah made reference to the sacrifice of Christian babies and infants.
'When I told you that you were confusing the Torah with The Protocols of the Elders of Zion, ... you insisted "it's in the Torah - it's in there!" (It isn't).'
Hebes is a derogatory name for a Jewish person, though it has been reclaimed by young and hip members of the faith in recent years.
But this was not the end of the claims made by the screenwriter.
'Listen to his songs! Imagine. I hate that f***ing song. I'm glad he's dead.'
But he was much more angry when talking about his former partner, with whom he had a protracted courtroom battle.
It is alleged he said: 'I want to f*** her in the a** and stab her while I'm doing it.'
And talking about executive Emanual, whose William Morris Endeavor Agency is the world's largest talent group, he claims he said: 'He's a c*** Jewboy.'
However the Braveheart actor has been quick to fire back and label all of his former creative partner's claims as lies.
In fact he claims they had a heated argument because he turned up at his mansion without a script after 15 months of working together, and that he had in fact been developing the project for a decade before they became collaborators.
He said: 'I have your letter. I am not going to respond to it line by line, but I will say that the great majority of the facts as well as the statements and actions attributed to me in your letter are utter fabrications.
'I would have thought that a man of principle, as you purport to be, would have withdrawn from the project regardless of the money if you truly believed me to be the person you describe in your letter. I guess you only had a problem with me after Warner Brothers rejected your script.
'I will acknowledge like most creative people I am passionate and intense.
'I was very frustrated that when you arrived at my home at the expense of both Warner Brothers and myself you hadn’t written a single word of a script or even an outline after 15 months of research, meetings, discussions and the outpouring of my heartfelt vision for this story.
'I did react more strongly than I should have.
I promptly sent you a written apology, the colourful words of which you apparently now find offensive. Let me now clearly apologize to you and your family in the simplest of terms.