From Halopedia, the Halo wiki
Emil Rukavina was a human who listened to Benjamin Giraud's Hunt the Truth audio journal in 2558. After Giraud's entries revealed the UNSC wasn't telling the truth about the Master Chief's history, Rukavina mailed Giraud an audio email where he suggested Giraud leave the matter alone. He felt that lies were the only thing holding humanity together post-war, and that not knowing the truth was an acceptable sin if it would keep people from descending into chaos.
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