Why did Moses (peace be upon him) ask for the untying of "a" knot from his tongue instead of untying the entire knot of his tongue, even though he knew that Allah Almighty said to him: (He said, "You have been granted your request, O Moses")?

Scholars differ on the meaning of "min" (مِنْ) in Musa's (peace be upon him) statement: "And untie a knot from my tongue" (waḥlul 'uqdatan min lisānī), holding two views:

The first view is that it is for partiality (tab'iḍiyyah), meaning that Musa (peace be upon him) asked his Lord to remove one of the knots from his tongue. This is supported by the indefiniteness and singular form of the word "knot" ('uqdah), and by Pharaoh's statement about him: "and he can hardly express himself clearly" (wa lā yakādu yubīnu), and Musa's own statement: "he is more eloquent in speech than I" (huwa afṣaḥu minnī lisānan).

The second view is that "min" (مِنْ) is an extra particle (zā'idah), and the meaning is: "Untie the knot of my tongue." Allah answered his request and removed the entire knot. As for Pharaoh's statement: "and he can hardly express himself clearly," it can be responded to in two ways: either Pharaoh meant that Musa could not articulate his argument clearly, or he was criticizing him for what he was like before the knot was removed.