unlettered person as a single reciter, the prayer of neither one of them is valid, because the unlettered person intended to lead the prayer while he has become solitary.

Section: If a reciter prays behind someone whose condition he does not know during a prayer in which recitation is silent, his prayer is valid; because the outward appearance is that no one advances to lead unless he is proficient in recitation, and the outward appearance has not been violated. He recited silently in a place of silent recitation. If he recited silently in a prayer of audible recitation, there are two views regarding this: One of them is that the prayer of the reciter is not valid. This was mentioned by al-Qadi, because the outward appearance is that if he were proficient in recitation, he would have recited audibly. The second is that it is valid, because the outward appearance is that no one leads people in prayer unless he is proficient in recitation; his silence might be due to forgetfulness, or ignorance, or because he does not know anything more than al-Fatihah, so the prayer is not invalidated by mere probability. If he says, "I did recite during the silent portion," the prayer is valid according to both views, because the outward appearance is that he is truthful. It is recommended to repeat the prayer as a precaution against him being a liar. If he recited silently in a prayer of silent recitation, then said, "I did not recite al-Fatihah," he and those behind him must repeat it. It has been narrated from Umar, may Allah be pleased with him, that he led them in Maghrib prayer, and when he had finished, he said, "Did you not hear me recite?" They said, "No." He said, "Then I did not recite it in myself," and he repeated the prayer with them.

Section: Whoever leaves out a letter of al-Fatihah due to inability, or replaces it with another, such as one with a lisp (al-althagh) who turns the 'ra' into a 'ghayn', or one with a stutter (al-arat) who merges one letter into another, or makes a grammatical error (lahn) that changes the meaning, such as one who gives a kasrah to the 'kaf' in 'iyyaka' or a dammah to the 'ta' in 'an'amta', and is unable to rectify it, is like the unlettered person; it is not valid for a reciter to follow him. It is permissible for each of them to lead his like in prayer, because they are both unlettered, so it is permissible for one of them to follow the other, just like two who do not know anything. If he is capable of rectifying any of that but does not do so, his prayer is not valid, nor is the prayer of the one who follows him.