Tafsir of Yunus 10:79

{What you have brought} Ma (what) is a relative pronoun acting as the subject (mubtada’), and al-sihr (the magic) is the predicate (khabar). That is: "That which you have brought is the magic," not what Pharaoh and his people labeled as magic from among the signs of Allah.

It is recited: (A-al-sihr) as an interrogative. According to this reading, ma is interrogative, meaning: "What is this thing you have brought? Is it magic?"

‘Abdullah recited: (Ma ji’tum bihi sihr). Ubayy recited: (Ma ataytum bihi sihr). The meaning is: "It is not what I have brought."

{Indeed, Allah will invalidate it} He will erase it or demonstrate its falsehood by manifesting the miracle over the sleight of hand.

{Allah does not set right the work of the corrupters} He does not establish it nor make it endure; rather, He brings destruction upon it.

{And Allah verifies the truth} He establishes and confirms it.

{By His words} By His commands and decrees. It is also recited: (bi-kalimatihi), meaning by His command and His will.

{But no one believed Moses, except [some] youths among his people, out of fear of Pharaoh and his establishment, that he would persecute them. And indeed, Pharaoh was haughty within the land, and indeed, he was of the transgressors.}