in the guise of truth: outwardly it is truth, but inwardly it is falsehood. Then Allah Most High said:
“and conceal the truth while you know.” [al-Baqarah: 42]
There are two views here.
According to one view, He forbade them to combine the two acts, and the conjunction “and” indicates their joint occurrence—a usage the Kufan grammarians call wāw al-sarf. An example is the expression, “Do not eat fish and drink milk together.” Likewise, Allah Most High said:
“while Allah has not yet made evident those of you who strive and made evident those who are steadfast.” [Āl ‘Imrān: 142]
This is according to the reading in which the second verb is in the subjunctive mood. The same applies to His words:
“Or He may destroy them for what they have earned, though He pardons much. * And those who dispute concerning Our signs would know that they have no escape.” [al-Shūrā: 34–35]
Again, this is according to the reading with the verb in the subjunctive mood. On this interpretation, the second verb, in His words “and conceal the truth,” would be subjunctive, while the first would be jussive.
According to the other view, however, this is the coordinating conjunction “and,” which places the conjoined expression under the same grammatical ruling as the expression preceding it. He would thus have forbidden both acts without making their joint occurrence a condition, as when one says, “Do not disbelieve, steal, or commit fornication.”
This is the correct view, as in the words of Allah Most High:
“O People of the Book, why do you mix truth with falsehood and conceal the truth while you know?” [Āl ‘Imrān: 71]
Had He condemned them for combining the two acts, He would have said wa-taktumū al-haqq (“and conceal the truth”), without the final nūn. That verse is parallel to this one.
In statements of this kind, when the intention is to prohibit each of the two acts, the negative particle may be repeated, as when you say, “Do not disbelieve, do not steal, and do not commit fornication.” An example is the statement of Allah Most High:
“O you who believe, do not consume one another’s wealth unjustly, but only through trade by mutual consent. And do not kill yourselves.” [al-Nisā’: 29]