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Someday, I was reading in a site…, I saw the name Jafar al Kazab.
Its name was written against the name of Imam Jafar al Sadiq(a.s.).
He was Jafar bin Ali, the son of Ali al-Hadi, the 10th imam. He was called "al-Kathhab" or "the Liar" because he denied the existence of Muhammad al-Mahdi and wanted to takeover the imamate for himself.
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