Salam Dear Brother,
Thank you for your question and for contacting Ask About Islam
After consulting with one of our scholars who is versed on the subject, he gave the following answer:
“You are advised to refer to the Message of the Quran by Muhammad Asad for an explanation of this verse. He came from a Jewish background, and had been schooled in the Jewish and Christian scriptures, besides the Quran.”
An internet search on the book (The Message of the Quran) by Muhammad Asad produced this result:
Muhammad Asad is a Jew who converted to Islam and this is what he says about this verse:
This statement is connected with the preceding verse, which speaks of the erring followers of earlier revelation. The charge of shirk (“the ascribing of divinity [or “divine qualities”] to aught beside God”) is leveled against both the Jews and the Christians in amplification, as it were, of the statement that they “do not follow the religion of truth [which God has enjoined upon them]”.
As regards the belief attributed to the Jews that Ezra (or, in the Arabicized form of this name, `Uzayr) was “God’s son”, it is to be noted that almost all classical commentators of the Quran agree in that only the Jews of Arabia, and not all Jews, have been thus accused.
(According to a Tradition on the authority of Ibn `Abbas – quoted by Tabari in his commentary on this verse – some of the Jews of Medina once said to Muhammad, “How could we follow thee when thou hast forsaken our Qiblah* and dost not consider Ezra a son of God?”
(*[Qiblah in arabic] when the Muslims changed the direction of worship i.e. from Bayt Al Maqdis [in Jerusalem] to Masjid Al-Haram in Makkah)
On the other hand, Ezra occupies a unique position in the esteem of all Jews, and has always been praised by them in the most extravagant terms.
It was he who restored and codified the Torah after it had been lost during the Babylonian Exile, and “edited” it in more or less the form which it has today; and thus “he promoted the establishment of an exclusive, legalistic type of religion that became dominant in later Judaism” (Encyclopaedia Britannica, 1963, vol. IX, p. 15).
Ever since then he has been venerated to such a degree that his verdicts on the Law of Moses have come to be regarded by the Talmudists as being practically equivalent to the Law itself: which, in Quranic ideology, amounts to the unforgivable sin of shirk, inasmuch as it implies the elevation of a human being to the status of a quasi-divine law-giver and the blasphemous attribution to him – albeit metaphorically – of the quality of “sonship” in relation to God. Cf. in this connection Exodus iv, 22-23 (“Israel is My son”) or Jeremiah xxxi, 9 (“I am a father to Israel”): expressions to which, because of their idolatrous implications, the Quran takes strong exception.
(Asad, Message of the Quran)
I hope this helps answer your question.
Salam and please keep in touch.