Al-An'am: (147) "So if they deny you, then say..."

(So if they deny you), meaning the Jews, as Mujahid, al-Suddi, and others have stated. This is what the apparent context necessitates, as they are mentioned more closely, and the polytheists are mentioned afterwards under the label of polytheism. It is also said that the pronoun refers to the polytheists.

Based on the first interpretation: If the Jews deny you regarding the aforementioned ruling and persist in their claim of the ancient nature of the prohibition, (then say) to them, (your Lord is the possessor of great, vast mercy); He does not take you to task for every sin you commit, but grants you respite for some of them. (And His might shall not be turned back), meaning His punishment cannot be averted at all, (from the criminal people). Do not, therefore, deny what has occurred from the Exalted regarding the prohibition of some wholesome things upon you as a punishment and a restriction.

Based on the second interpretation: If the polytheists deny you regarding the detailed rulings of what is lawful and what is forbidden, then say to them, "Your Lord is possessor of vast mercy." He does not hasten punishment upon you for your denial, so do not be deceived by that, for it is a respite, not a neglect.

It is also said: It is possible that the meaning is that He, the Exalted, is the possessor of vast mercy, so He will show mercy to me by granting me success in my belief, and thus your denial will not harm me. Rather, it will harm you, because He does not avert His might from the criminal deniers, or He will show mercy to me by taking vengeance upon you, and He does not avert His might from you. There is some remoteness in this view.

It is further said: The meaning is that He is the possessor of mercy for the obedient and possessor of severe might over the criminals. The words of the Exalted, (And His might shall not be turned back), were placed in its stead to include the warning of the descent of punishment upon them, while indicating that it will surely reach them without any obstacle to turn it away from them at all.