or to clothe them, or to free a slave. But whoever cannot afford this must fast for three days. That is the expiation for the oaths you make. So keep your oaths. This is how Allah makes His verses clear to you, so that you may be grateful.” [al-Ma'idah 5:89] In Ibn Mas'ud’s recitation: “But whoever cannot afford this must fast for three consecutive days.” (1)
Thus, if someone were to recite in the prayer, “must fast for three consecutive days,” his prayer would be invalid according to this view.
They say: This phrase is not legally regarded as part of Allah’s speech, even though it may in fact be part of Allah’s speech. Yet we do not legally treat it as part of Allah’s speech; it is therefore deemed to be human speech. The Prophet, peace and blessings be upon him, said: “Nothing of people’s speech is suitable in this prayer.” (2)
However, when you reflect on this view, you find it weak. How can it be deemed human speech when it is authentically established that the Prophet, peace and blessings be upon him, recited it? This is especially so with the recitation of Ibn Mas'ud, concerning whom the Messenger, peace and blessings be upon him, said: “Whoever wishes to recite the Quran fresh as it was revealed—or, in another wording, tender as it was revealed—let him recite according to the recitation of Ibn Umm 'Abd.” (3)