Translation of the verse 91 from Surah Al-An‘am : Number of verses 165 - - page 139 - Part 7.
They (the Jews, Quraish pagans, idolaters, etc.) did not estimate Allah with an estimation due to Him when they said: "Nothing did Allah send down to any human being (by inspiration)." Say (O Muhammad SAW): "Who then sent down the Book which Musa (Moses) brought, a light and a guidance to mankind which you (the Jews) have made into (separate) papersheets, disclosing (some of it) and concealing (much). And you (believers in Allah and His Messenger Muhammad SAW), were taught (through the Quran) that which neither you nor your fathers knew." Say: "Allah (sent it down)." Then leave them to play in their vain discussions. (Tafsir Al-Qurtubi, Vol. 7, Page 37).
And they did not appraise Allah with true appraisal when they said, "Allah did not reveal to a human being anything." Say, "Who revealed the Scripture that Moses brought as light and guidance to the people? You [Jews] make it into pages, disclosing [some of] it and concealing much. And you were taught that which you knew not - neither you nor your fathers." Say, "Allah [revealed it]." Then leave them in their [empty] discourse, amusing themselves.
(6:91) They did not form any proper estimate of Allah when they said: 'Allah has not revealed anything to any man.' *59 Ask them: 'The Book which Moses brought as a light and guidance for men and which you keep in bits and scraps, some of which you disclose while the rest you conceal, even though through it you were taught that which neither you nor your forefathers knew -who was it who revealed it?' *60 Say: 'Allah!'- and then leave them to sport with their argumentation.
*59). In the light of the foregoing discussion and commentary, it is quite evident that this statement comes from the Jews. Since the Prophet (peace be on him) had asserted that he was a Prophet and that a Book had been revealed to him, the unbelieving Quraysh and other polytheists of Arabia naturally used to approach the Jews and the Christians - who believed in the Prophets and in the Scriptures - and tried to solicit a candid answer from them as to whether God's words had indeed been revealed to Muhammad (peace be on him). Whatever answer they gave was then disseminated on all sides by the active opponents of the Prophet (peace be on him) in order to create revulsion against Islam. This is the reason for mentioning, and then refuting, this statement by the Jews, which had been used by the opposition as an argument against Islam.
One might wonder how a Jew, who believes in the Torah as a revealed Book of God, could say that God had revealed nothing to anyone. At times blind obstinacy and bigotry cause people to resort to arguments which strike at the roots of their own belief. These people were bent upon denying the prophethood of Muhammad (peace be on him), and this fanaticism had come to dominate them so much that they went so far as to deny the very institution of prophethood.
To say that peopte have not formed any proper estimate of God means that they have erred grossly in assessing His wisdom and power. Whoever says that God did not reveal knowledge of Reality and the code for man's guidance has fallen into one of two errors. Either he considers it impossible for man to become the recipient of God's revelation, and this constitutes a gross misjudgement of God's power, or he thinks that even though God has equipped man with intelligence and with the power to act as he chooses, He has nevertheless made no arrangement for his guidance, but has left him in this world altogether unguided and thus conferred upon him the right to behave in any way he likes. This is obviously a misjudgement of God's wisdom.
*60). The revelation of the Torah to Moses (peace be on him) is adduced by way of evidence since the Jews, to whom this response is addressed, believed that it had been revealed. It is obvious that their recognition of the Torah as the Book revealed to Moses negated their standpoint that God had never revealed anything to any human being. Their belief in the Torah at least proved that revelation to man is possible, and had actually taken place.