As Muslims we believe that the bible has been corrupted. My friend who is a kafir asked me why do scholars like Dr. Zakir Naik use the bible to prove Islam right if the bible is corrupt?
Quran is the updated version of bible, torah... And all the messages which are passed to mankind from god. And as per Quran it us the last message passed and combined all messages together which are passed to Mohammed peace be upon him.
As a Muslim everyone have a responsibility to pass the messages(of Quran) to all humans including non-Muslims. Dr Zakir Naik did research on all the holy books. Not just bible even bhagavatgeeta (Hindu holy book) torah etc.
Its all about factual speech. If anyone makes a statement with facts or proofs. People listens to them.
Dr Naik does same. If some one speaks makes a statement about a religion before a particular religious person with out a fact. He will definitely doubt it. But if statement is made with proofs. He will agree or at least think or try validating it.if he finds its true. He will believe the person.
The main intention is not to prove bible wrong. But Quran is updated and is much better than bible. Listen to his speeches and you will find an answer.
As a Muslim we respect Jesus pbuh, Moses pbuh and all prophets who are before Muhammad pbuh.