Chapter on the Rulings on Forgetfulness (Ahkam al-Sahw)

From him, from Musa ibn ‘Umar ibn Yazid from Ibn Sinan from Abu Sa‘id al-Qammat, who said: I heard a man asking Abu Abdillah عليه السلام, peace be upon him, about a man who experiences cramping in his stomach, discomfort, or pressure from urine while he is in an obligatory prayer during the first, second, third, or fourth rak‘ah. Imam عليه السلام said: "If something like that happens to him, there is no harm in him leaving for his need, then performing ablution, and returning to his place of prayer where he was praying, and he should continue his prayer from the point where he left for his need, as long as he has not invalidated the prayer by speaking." He (narrator) said: “I asked, ‘Even if he turned to the right or left, or turned away from the qiblah?’" Imam عليه السلام said: "Yes, all of that is permissible. It is like the case of a man who forgets and leaves during one rak‘ah, or two, or three of an obligatory prayer. All that is required of him is to continue his prayer based on what he had already prayed." Then Imam عليه السلام mentioned the forgetfulness of the Prophet صلى الله عليه وعلى آله وسلم. peace be upon him and his family.