On Oct. 29,1961, Mohammed was arrested for failure to report to Elgin State Hospital. The following day, on his 28th birthday, Mohammed was transferred to Federal Correctional Institution, Sandstone to begin a term for having refused induction into the United States military. He could have performed community service, but his father pressed him to accept the jail time. He spent most of that time studying the "Quran", the main Islamic holy book. He became convinced that the Nation of Islam had to change. In 1963 he was released from prison and resumed studies under Muhammad Abdullah. Close also to Malcolm X, who the NOI had expelled, he found that by this time his viewpoints deviated significantly from those of his father, whom he no longer believed to be a prophet. Because of this conclusion, he was excommunicated five different times, yet by 1974, he was returned permanently to the NOI.