• I asked Ishaq, and I said: A man prayed alone and forgot to recite the surah? He said: "He recites in the next [rak'ah] the Hamd and a surah."

• I asked Ishaq again about a man who forgot the recitation in the first two [rak'ahs] but recited in the last two; is his prayer valid? He said: "It is valid."

• Ishaq was also asked about a man who forgot the recitation in the first rak'ah of the Dhuhr [prayer]? He said: "He recites in the second [rak'ah] the Hamd and Surah Maryam, then the Hamd and a surah once."(1) It was said: What if he forgot the recitation in the first two [rak'ahs]? He said: "He recites in the last two; in every rak'ah the Hamd and a surah once." I said: And he does not recite in each rak'ah twice? He said: "No, for there is no recitation in the last two [rak'ahs]."

• Ishaq was asked again about a man who forgot the recitation in the first rak'ah of the Dhuhr? He said: "If he recited in the three remaining rak'ahs, it suffices him."

• I heard Ishaq again saying: "The sunnah has already been established: if one forgets to recite in the first rak'ah of the Dhuhr, or the 'Asr, or all of the prayers, and he remembers while he is in the second rak'ah, he repeats the Fatihah of the Book in the second rak'ah and a surah—meaning, for this rak'ah he is currently in—then he repeats the Fatihah of the Book and a surah as a substitute for what he missed; just as 'Umar ibn al-Khattab, may Allah be pleased with him, did when he forgot to recite the Fatihah of the Book in the Maghrib prayer, so he did in the second rak'ah as we described. And even if there were no sunnah in this as we described, it would be closer to the established sunnah to recite in the second. If he forgets in the first rak'ah of the Subh [prayer], then it is the same; he recites in the second twice, and it suffices him. And if he forgets in the first two, he recites in the last two; just as 'Alqamah, al-Aswad, and those after them said."