At the begining of the lecture Dr. Zakir Naik and Ahmed Dedar and other defends themselves against such argument as follows
Muslims does not believe the presend Bible contain the original message Prophet Jesus (PBUH). Nor the old testimony contains the original message of Prophet Muses (PBUH). Muslims also belive those scirptures were valid only upon the duration of those prophets.
But if we want to argue with the Christian/Jews that Koran is the last and final testemant they will not believe us. Likewise Hindus, Buddhist.
So in order to prove them the Koran is the final and ultimate revealation they quote from their corrrupted scriptures.
Likewise Dr. Zakir Naik also quote verses of Ajurbadh, Vabishapurana, bedh, Tripitok, and other scriptures in the world.
So there is nothing worng to convience the nonmuslims by using thier own scriptures.
By the way, Ahmed Dedar and Zakir Naik are not the inventor of this method of giving dawah.
It is the zionist, free missionary, athiest, hindus, christian and Jews who were, are and will be writing millions of books insulting Holy Koran, and Prophet Muhammad (PBUH). They have done it in the last 1400 years and they will do so until the day of judgement.
Ahmed dedar was the first person to successfully defeat those criminals by using their own belief systems. Before, insulting muslims, our prophet and our Koran, they should think aobut their own dirty beliefs. Dr. Zakir Naik is continuing the mission of Ahmed dedar.
We have to contiue it if we want to survive. It has been imposed on muslims by the zionist, athiest, Hindus, Christians and Jews.
Do not say Dr. Zakir Naik, Ahmed dedar introduces Bidah. They are defending the speech of Allah against the enemy of Allah.
May Allah Grant paradise to Ahmed Dedar. May Allah bless Dr. Zakir Naik and bless our community with more and more Zakir Naik.
Salam