Shaykh Ibn Uthaymeen (rahimahullaah) said:

And belief in the [Revealed] Books comprises four things

Firstly: That we believe that Allaah, the Most High, sent down books upon the Messengers, and that they are from Allaah. However, we do not believe that the books [currently] present in the possession of these nations are the [very] books that are from Allaah, because they are distorted, changed. However, we believe the original revealed Book [sent down to] the Messenger is truly from Allaah.

Secondly: That we believe in the correctness of what is in them (i.e. the revealed books in general) of information (akhbaar), like (for example) the information in the Qur'an, and the information in what has not undergone distortion or change from the previous books.

Thirdly: That we believe in what they contain of rulings (ahkaam), when they (the rulings) do not oppose our Sharee'ah, [based] upon the [particular] viewpoint that the legislation of those who preceded us is also a legislation for us, and that is the truth.

Fourthly: That we believe in what we know of their names, such as "The Qur'an" (the Recital), "the Tawrat" (the Torah), "the Injeel" (the Gospel), "the Zaboor (Scrolls) [of Dawud]" , "the Suhuf (Scrolls)" of Ibraaheem, and "the Suhuf (Scrolls)" of Moosaa.

And if a man was to say: I do not believe that there is a book called "Tawraat", then he is a disbeliever, because faith in Allaah comprises faith in the Books.

Source: "Mu'jam at-Ta'reefaat wad-Dawaabit wat-Taqseemaat wal-Fawaa'id Fil-Musannafaat al-I'itqaadiyyah Lish-Shaykh Ibn al-Uthaymeen", pp. 94-95.