The ulema in general divide people into two categories while studying books of God other than the Quran.
The first group is ordinary people, those who have no knowledge and those who are weak in faith. They are recommended not to study these books so that they will not be confused by that which has been introduced into them of falsehood, and so that they will not be distracted by something that is of no benefit.
The second category of people is those who are well versed in knowledge, who use these books to debate with the Jews and Christians, and to establish proof against them. In this case the fear of confusion is less, because the one who is well versed in knowledge has the ability to recognise the falsehood that has been introduced into these books and to be cautious of it, and to refute it and warn others against it.
More details can be found here.
A relevant Hadith for us is:
It was narrated from Jaabir ibn ‘Abdullah (may Allah be pleased with
him) that ‘Umar ibn al-Khattaab (may Allah be pleased with him) came
to the Prophet (blessings and peace of Allah be upon him) with some
written material he had got from one of the people of the Book. He
read it to the Prophet (blessings and peace of Allah be upon him), and
he got angry and said: “Are you confused (about your religion), O son
of al-Khattaab? By the One in Whose hand is my soul, I have brought it
(the message of Islam) to you clear and pure. Do not ask them about
anything, lest they tell you something true and you disbelieve it, or
they tell you something false and you believe it. By the One in Whose
hand is my soul, if Musa were alive, he would have no option but to
follow me.”
Narrated by Ahmad (14736)
It is a fact that the Zubur, Torah and Injeel are the books of Allah and as Muslims we have to believe them to be so. But it has also said in the Quran:
So woe to those who write the "scripture" with their own hands, then
say, "This is from Allah," in order to exchange it for a small price.
Woe to them for what their hands have written and woe to them for what
they earn.
Quran (2:79)
Thus we have been informed that they have been corrupted. We believe in the parts that are in line with the Quran. We reject the parts that go against the Quran. For others, we neither accept nor deny as knowledge of it has not been given to us.
