I simply refuse to accept that fact.
He states that his father "never lied to him".
His father denies the Holocaust was as severe as portrayed. His father believes Israel is the root cause of the Middle East's generations-old problem.
Anyone that can sit down and view "Obsession" can see the correlation here.
That said, I cannot believe that Mel Gibson cares whether he works another day in his life. The proceeds from Passion of Christ by itself should ensure he doesn't need to care.