3:3  He has revealed upon you this Scripture with the Truth, confirming that which was before it; and He revealed the Tawrāt and the Injīl,
3:4  in the past as a guidance to mankind, and He has revealed the Discrimination. Surely those who disbelieve in the Messages of Allāh, for them is a terrible punishment. And Allāh is Exalted in Might, Possessor of power of retribution.

3:3-4 The revelation of the Qur’ān was not complete at the time of revelation of this verse, yet Allāh chose to refer to the Qur’ān as kitāb or Book to imply in course of time it would be completed and compiled into a book. It was revealed with ‘truth’, a term that connects not only to its content, but also to its source, process of revelation, coherence and purpose.
As a rare of example of the Qur’ān’s worldview, it verifies the truth in earlier scriptures, particularly in the Tawrāt and the Injīl, vestiges of which are still available in the form of the Torah and the Bible. Although ‘Isā came to confirm Mūsā’s book Tawrāt (3:50; 5:46; 61:6), it must be remembered that the Old Testament is not necessarily the Torah used by the Jews. The Jewish interpretation of Torah has two sections, the Torah Shebiksav (the written Torah) and Torah Sheb’al Peh (the Oral Torah, that eventually was compiled into what is called Talmud). The written Torah has 24 books, only 5 of those books were revealed to Moses, various saints wrote the rest.
Similarly, popularly understood four Gospels in the New Testament are not the same Injīl (Evangel or Gospel) revealed by Allāh to ‘Isā.  The original Injīl was invariably in Aramaic, the language spoken by Jesus. The precursor of the present day Bible was translated from the original Aramaic into Greek and later translated into English. The current Gospels contain remnants of original Injīl, but for all practical purpose, the original Injīl has long been lost. The scope of this commentary would not permit us to go into the details of early Christianity and compilation of the Bible. It must be understood that when the Qur’ān testifies the Tawrāt or the Injīl were guidance for mankind it is not referring to the present versions. 
The Qur’ān is referred to here as furqān (lit. discrimination, 2:185; 25:1). The Qur’ān not only distinguishes between what is right and wrong in terms of faith but also between perfect and corrupt in terms of what was revealed. The term al-furqān, as explained by Ibn Kathīr, Tabari, Zamakhsharī, Suyuti, Baidāwi and many other classical commentators, refers to heavenly books that distinguish between the truth and falsehood, guidance and misguidance, right and wrong, lawful and unlawful. Rāzī’s explanation of the term comes close to the biblical ‘knowledge of good and evil’. At-Tabari connects the term to ethics. Abduh as quoted by Rida explains furqān is the reason by which man discern between truth and falsity.

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