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Greta Van Susteren sat down with Saeed Abedini, the Christian pastor who was freed from Iran, for his first and only interview.

Abedini opened up about his ordeal in an Iranian prison, from torture behind bars to his release and return to America.

Abedini revealed that he was interrogated and tortured after he refused to sign documents implicating him in crimes that he did not commit.

In addition to being physically and psychologically abused, Abedini said he saw terrible things happen to other prisoners, such as Sunni Muslims being publicly executed.

Despite those trials and tribulations, Abedini said the most difficult part of being in jail was finding how to pass the countless hours.

That changed somewhat when he was transferred to the same cell as former U.S. Marine Amir Hekmati, which helped pass the time.

"When they sent me to the other solitary - which Amir Hekmati, the Marine, was over there," Abedini said. "They bound my eyes, they took me to his room, and up in there, I think, for almost 60 days with Amir."

"First, when I removed my eye band, and I saw Amir, I got very heartbroken to see what they did to our Marine," Abedini said, explaining that Hekmati had black eyes, and he was very thin and weak.

Other than speaking with Hekmati, Abedini said he spent much of his confinement in prayer.

"Mostly I was praying," Abedini said. "The best thing I could do over there was [pray]."

Watch the powerful "On The Record" interview above.

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