When, however, the negative particle is not repeated, this is because one of the two acts is connected with the other—for example, when one entails the other, as in the expression: “Do not disbelieve in Allah and deny His prophets,” and similar expressions.
Cases in which the two acts can occur together without anything objectionable in their conjunction, yet the prohibition applies to both, are rare in speech. Accordingly, the second verb is seldom subjunctive; more commonly, both verbs are jussive.
This helps explain why the stronger interpretation of His words “and mix” is that “and” is a coordinating conjunction and the verb is jussive. The negative particle was not repeated because one act is connected with the other and entails it. Although prohibiting the act that entails another includes prohibiting the act it entails, one might suppose that the latter is not itself intended by the prohibition, but is included only as a matter of logical necessity.
For this reason, people have disagreed over whether commanding something also commands whatever it necessarily entails, and whether it prohibits its opposite. Yet they agree that the commanded act can only be performed by doing whatever it necessarily entails and refraining from its opposite.
The disagreement arises because the one issuing the command may not intend to command those necessary consequences or to prohibit the opposite act. Thus, if he punishes the person charged with the command, he punishes him only for failing to perform the commanded act—not for failing to do what it entails or for doing its opposite.
This is the issue commonly expressed by the maxim: “Whatever is indispensable to fulfilling an obligation is itself obligatory.”
Some people have erred concerning this issue, dividing such prerequisites into those beyond the legally accountable person’s ability—such as soundness of the limbs, the number of worshippers at Friday prayer, and similar things he cannot secure—and those within his ability, such as travelling the distance required for Hajj, washing part of the head during ablution, and abstaining