Therefore, when you petition Allah, do not say, “if You will.”

As for the Prophet’s words ﷺ, “lā baʾs, ṭahūr, in shāʾ Allāh,” the addition of “in shāʾ Allāh” is because the statement is informative and meant as a hopeful forecast. He first says, “lā baʾs” (“no harm”), as though denying that any real injury has occurred, and then adds, “in shāʾ Allāh,” for every matter is subject to Allah’s will. From this ḥadith we learn that whoever visits a sick person should, upon entering, say: “lā baʾs, ṭahūr, in shāʾ Allāh.”

908 – Abū Saʿīd al-Khudrī (may Allah be pleased with him) reported that Gabriel came to the Prophet ﷺ and said, “O Muḥammad, are you unwell?” He replied, “Yes.” Gabriel said, “In the Name of Allah I perform ruqyah for you, against everything that harms you, from the evil of every soul and every envious eye. May Allah cure you. In the Name of Allah I perform ruqyah for you.” Reported by Muslim.

Explanation
He then cited the ḥadith of Abū Saʿīd al-Khudrī (may Allah be pleased with him): Gabriel came to the Prophet ﷺ and asked, “Have you fallen ill?”—meaning, are you sick?—and the Prophet replied, “Yes.” Gabriel said, “In the Name of Allah I perform ruqyah for you, against everything that harms you, from the evil of every soul or the eye of an envier.”