“Then they would say, ‘Our Lord, if only You had sent us a messenger, so that we might follow Your verses and be among the believers.’” The apodosis of “if only” is omitted; that is: We would have hastened their punishment. In other words, had they not been able to cite the failure to send them a messenger as an argument, We would have hastened to punish them for their disbelief. It is also said that the meaning is: We would not have sent you to them as a messenger; rather, We sent you to them so that people would have no argument against Allah after the messengers.
“But when the truth came to them from Us, they said, ‘Why has he not been given the like of what Moses was given?’ Did they not previously disbelieve in what Moses was given? They said, ‘Two sorceries supporting one another,’ and said, ‘We disbelieve in both.’ (48) Say, ‘Then bring a Book from Allah that is a better guide than these two, and I will follow it, if you are truthful.’ (49) But if they do not respond to you, then know that they are only following their desires. And who is further astray than one who follows his desire without guidance from Allah? Indeed, Allah does not guide the wrongdoing people. (50)”
“But when the truth came to them from Us,” meaning Muhammad, peace and blessings be upon him, “they said”—that is, the disbelievers of Mecca—“Why has Muhammad not been given the like of what Moses was given?” That is, signs such as the radiant hand and the staff. It is also said: the like of what Moses was given, namely, a book all at once. Allah, Most High, said: “Did they not previously disbelieve in what Moses was given?” That is, they disbelieved in the signs of Moses just as they disbelieved in the signs of Muhammad. “They said, ‘Two sorceries supporting one another.’” The people of Kufa recited it as “two sorceries,” referring to the Torah and the Quran: “supporting one another,” meaning that each sorcery strengthens the other. The mutual support was attributed to the two sorceries by way of figurative expression. Al-Kalbi said: They made this statement when they sent to the leading Jews in Medina and asked them about Muhammad. The Jews informed them that his description was found in their book, the Torah. They returned and told them what the Jews had said, whereupon they said, “Two sorceries supporting one another.” Others recited it as “two sorcerers,” referring to Muhammad and Moses, peace be upon them both, because mutual support is more fittingly ascribed to people and their actions than to books. “And they said, ‘We disbelieve in both.’”
“Say, O Muhammad, ‘Then bring a Book from Allah that is a better guide than these two,’” meaning, than the Torah and the Quran, “‘and I will follow it, if you are truthful.’”
“But if they do not respond to you,” that is, if they do not bring what you have demanded, “then know that they are only following their desires. And who is further astray than one who follows his desire without guidance from Allah? Indeed, Allah does not guide the wrongdoing people.”