BEVERLY HILLS, Calif. – John Debney is used to writing movie scores for comedies like "Liar, Liar" and "Bruce Almighty," but he admits that composing the score for Mel Gibson's powerful movie "The Passion of the Christ" was the most difficult assignment of his life.

For it turned out to be a battle between good and evil that he had never experienced before in some 20 years in Hollywood.

"I don't think I will ever be given the opportunity to write again for a movie as powerful as this one," he said during a recent media interview in Beverly Hills.

"I was stretched every which way but loose," Debney said. "I was stretched by Mel Gibson. I was stretched by the Guy Upstairs and also I was stretched by the guy downstairs. What it did was completely strengthen my faith and I have realized something very interesting. I had never before subscribed to the idea that maybe Satan is a real person, but I can attest that he was in my room a lot and I know that he hit everyone on this production."

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Debney said that the battle he felt with Satan as he wrote the music became "really personal between us."

He went on to say, "I had all these computers and synthesizers in my studio and the hard drives would go down and the digital picture that lives on the computer with the music would just freeze on his [Satan's] face. Then the volume would go to ten and it would happen all the time.

"The first time it happened, it scared me," Debney said. "Once I got over the initial shock of that, I learned to work around it and learned to reboot the computers and so I would start talking to him.

"There was one day when I had been on the movie for about four months when it really became bad that day and a lot of things that were causing doubt in me and I had had enough. The computers froze for about the tenth time that day and it was about nine o'clock at night and so I got really mad, and I told Satan to manifest himself and I said, 'Let's go out into the parking lot and let's go.' It was a sea change in me. I knew that this was war. I am not a physical person, but I was really angry on this occasion.

"I am up on the second floor, and on the bottom floor of my building there are therapists, and they see patients until midnight, and their windows are right at the parking lot, and I was coming down the stairs, and I had had it. I had booted everything down and saved it and I was walking down the stairs and I was verbalizing and saying to Satan, 'Manifest yourself right now.' As I am walking out and saying, 'Come on, let's go now,' I looked over and I could see someone looking at me and I realized how silly I must have looked. He didn't manifest himself, but I wished he would have. It changed for me after that."

God works in mysterious ways

John Debney explained that he was first brought into the movie by Stephen McEveety, a producer on the movie.

"The way God works is very mysterious," he said. "This gentleman is a life-long friend who happens to work for Mel Gibson and Icon and he and I grew up on the same street together in Glendale, California."

This resulted in Debney writing some special music for the movie and Gibson then came over to his office to listen to it. The next thing he knew, he was hired to write the score.

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"If you were to draw up a list of composers who would have been perfect for this movie, I don't think I would be on it," he said. "It is a complete miracle that I became involved with the project and every day the thing that got me through was my faith prayer which was, 'Lord, if you want me to make it to the finish line, then help me make it to the finish line.'

"That was my journey. I started working with Mel Gibson and I found him to be incredibly intense," he said. "He's incredibly demanding but he was also incredibly collaborative.

When asked him what it was like to watch the horrendous suffering of Christ day after day, he replied, "It was very difficult and I can describe the process that I went through. I had to at times divorce myself from the visuals at times. You can imagine, day in, day out, you are watching this incredibly powerful journey that Christ went through, it was very difficult for me and I was able to get past it and realize that it was a movie; that really wasn't Him there although the movie was very powerful and beautiful and a wonderful representation of Him, so that kicked in and it was an intellectual process, although it would obviously still get the best of me from time to time.

"For instance, I would be working on a certain scene, like when Mary flashes back to the baby Jesus falling down, and I would see it 20 times, and then I would see if for the 21st time I would just start to weep because it is so elusive, the power of this film. That was way I would get through it. It was difficult; it was uplifting. I would sit there and try and write a piece of music on Jesus being hammered to the cross. So there has to be a little bit of a disconnect. I had to distance myself enough and trust that He would tell me what to do and everyone on the music say that day in and day out, it was extremely difficult.

"I would imagine that we all worked as hard as we ever could. We were all exhausted as we could ever be, but oddest thing was as exhausted and physically drained that I was, I never got tired. I would be exhausted and yet I would find myself in my studio at midnight.

"My studio is a lovely room and I have a work station with my keyboard. I write everything at a keyboard now. Technology has got so far in the last few years that I sit at the computer and realize the score. And what I mean by that is that I wrote and I orchestrate at the same time. So that when Mel Gibson comes and sits in the room, he will hear a piece of music that is fully orchestrated; it's synthesized orchestrated. He'll hear the obo, and then the clarinet and the strings, and so literally, I am composing note for note; instrument for instrument."

"So I have the screen in front of me with the visuals and then I have the speakers and computer screens that have all my synthesizer information on it. So my virtual orchestra is in a box and I just pick my instruments.

"What I was trying to do with the music was to write first of all the best that I could write and try to be true to the period, so I tried to utilize instruments from the period so there are a lot of ancient instruments in the music. In the bigger picture, I gave it all up to the Lord and whatever came out. I didn't have a lot to do with the writing of this music. I have done a lot of music, but literally things would just come out.

"I was tested. I once said to Mel, 'With every lash that Christ felt, I was feeling those lashes in my own way.' I was sorely tested."

He then talked about doubt.

"What happened with this movie was that I started to doubt myself," he said. "Mel started to doubt me, and there was a lot of it going around. You can imagine how important this film was to Mel and God bless him for having the courage to do it. But during my working with him musically, he would say things to me like, "It's really good, but I want it to be great.' And I had been up days … ."

Editor's note: Coinciding with the release of Mel Gibson's film "The Passion of the Christ," WorldNetDaily has issued one of the most extraordinary editions of its monthly Whistleblower magazine ever produced, titled "THE DAY JESUS DIED."

Read WorldNetDaily's extensive coverage of Mel Gibson's "The Passion of the Christ."