Tafsir of Ta-Ha 20:42

His saying, Exalted is He, "Go you and your brother with My signs," is an inauguration brought forth to clarify what is intended by [the aforementioned] "fashioning" [of him for My cause]. "And your brother" is the subject of an implied verb; that is, "And let your brother go, just as you have requested." It is also said that it is a conjunction joined to the hidden pronoun [in idhhab] which is emphasized by the explicit pronoun [in anta], for many a thing is valid as a dependent that is not valid independently.

"The signs" are the miracles. What is intended by them, according to some, are the hand and the staff, and the loosening of the knot [in the tongue]. According to Ibn Abbas, they are the nine signs. Others said: they are only the hand and the staff, and the usage of the plural for two is common. This is supported by the fact that when Pharaoh said to him, peace be upon him, "Bring a sign," he cast the staff and drew out his hand, and [Allah] said, "These are two proofs." Some have said: even though they were two, within each of them were various signs, as in His saying, "Clear signs, [among them] the Station of Ibrahim." For the staff turning into an animal is a sign, its being a massive serpent whose size cannot be estimated is another sign, the speed of its movement despite the enormity of its mass is another sign, and its being submissive to him, peace be upon him, such that he could place his hand in its mouth without it harming him is another sign, and then its returning to being a staff as it was is another sign. Likewise, the white hand: its whiteness in itself is a sign, its radiance is a sign, and its return to its original state is another sign. It is also said that what is intended is what he was given of miracles and revelation.

What the heart inclines toward is that it refers to the staff and the hand, due to what I have heard from [the evidence] supporting it, along with what has preceded: that after He commanded him to cast the staff and take it back after it turned into a serpent, the Glorified said: "And draw your hand to your side, it will come out white without disease—another sign," then He said, "Go to Pharaoh. Indeed, he has transgressed," without specifying anything other than those two signs, and without describing the loosening of the knot or anything else as a "sign." Furthermore, the ba is for accompaniment, not for causation; for the intention is their going to Pharaoh while accompanied by the signs, holding fast to them in executing the rulings of the message and completing the call, not merely the act of taking them and delivering them to him. This is evident in the realization of the signs at that time, whereas most of the nine had not yet occurred.

"And do not slacken" (wa lā taniyā)—from al-wanā, meaning languor or weakness. It is an intransitive verb; when it is made transitive, it is done so with fī or ‘an. Some of the Baghdadis claimed that it is a defective verb from the sisters of zāla (meaning "to remain/cease"), and holds its meaning, and Ibn Malik chose this view. In al-Siḥāḥ, it is said: "So-and-so does not yanī to do such-and-such," meaning he does not cease doing it. Perhaps this meaning is derived from the negation of languor. Ibn Wathab read it as wa lā taniay (with a kasra on the tā), following the vowel of the nūn. In the codex of Abdullah, it is lā tahnā (do not become weak), and the conclusion is the same: do not slacken.

"In My remembrance" pertains to that which befits Me of glorious attributes and beautiful actions when conveying My message and calling to My worship. It is said the meaning is: Do not slacken in conveying My message, for "remembrance" can be applied metaphorically to all acts of worship, and it is among the highest and greatest of them. This has been narrated from Ibn Abbas—may Allah be pleased with them both. It is also said: Do not forget Me wherever you go, and seek help and support through it, and know that no affair can be accomplished or made easy except through My remembrance.

Aaron was joined with Moses, peace be upon them, in the dual form of the second-person prohibition, based on the opinion that he was absent at that moment, [addressed together] for the sake of precedence, and there is no distance in that, as is not hidden.