Commentary Qur’an...
Commentary Qur’an: And when there came to them a Book : The context shows that “a Book” refers to the Qur'an. Qur’an: and aforetime they used to pray for victory against those who disbelieved : It appears that whenever the pagans of Arabia clashed with the Jews, the latter prayed for victory by the right of the Prophet, and by his prophethood and emigration; and that this was their usual custom before the advent of the Prophet, so much so that even the pagans knew it of them.
It all is implied in the word, “they used to”. Qur’an: but when there came to them that which they did recognize : They knew that Muhammad (s.a.w.a.) was the awaited Prophet, because all the attributes and particulars mentioned in their books fitted on him perfectly. And yet they denied his truth. Qur’an: Evil is that for which they sold their souls. . .
: “Baghyan “ ( بغياً = out of envy) is in accusative case, explaining the reason why they disbelieved in Muhammad (s.a.w.a.) even after recognizing him. What they did was “out of envy”, “that Allah should send down of His grace on whomsoever of His servants He pleases” was the object of their envy. “So they returned with wrath upon wrath”, that is, they returned doubly enraged.
It may also mean that they invited double wrath of Allah upon themselves - the first because they disbelieved in Torah and the second because they disbelieved in the Qur'an. The verse says that they were partisans of the Prophet long before he was born; they prayed to Allah for victory by his name and his Book. When the Prophet was sent and the Qur'an was revealed, they very well recognized that he was the Prophet in whose name they used to pray for victory, and whose coming they awaited.
But they were overwhelmed by envy and arrogance. No sooner did the Prophet begin his call then they denied his truth, and forgot all that they used to tell about the awaited prophet. It was not surprising as they had earlier disbelieved in Torah too. Thus they committed disbelief after disbelief, and invited the wrath of Allah upon themselves, not once but twice.
Qur’an: and they deny what is besides that : That is, they claim that they do not believe in any book other than Torah; but the fact is that they do not believe even in Torah. Qur’an: Say: “Why then did you kill Allah's prophets. . . ”: The conjunctive, “then”, serves to relate this question to their claim, “We believe in that which was revealed to us”.