31. My father said: `Ali ibn al-Hasan al-Kufi said, on the authority of his father al-Hasan ibn `Ali ibn `Abd Allah al-Kufi, on the authority of his grandfather `Abd Allah ibn al-Mughayrah, on the authority of Isma`il ibn Muslim that Al-Sadiq was asked about the prayer behind one who denies the decree of Allah, the Mighty and High. He said: “Then he should repeat all the prayers he has prayed behind him,”