The conditions that permit debating with the Christians
28-3-2006 | IslamWeb
Question:
I was surprised in one programme named Pall talk to discover that the Christians insult the Prophet, sallallaahu alayhi wa sallam, but I could not do anything as there were a great number of them whereas we were very few, only one or two persons. What should I do?
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His Slave and Messenger 
as well as that of his family and all his companions.
The enemies of Allaah can not do anything which would harm Islam except these kinds of insults. However, a Muslim should ignore these ignorant people so that he will not expose Islam to their insults. Allaah Says (what means): {And do not insult those who invoke other than Allaah, lest they would insult Allaah in enmity without knowledge.}[Quran 6:108]
Therefore, it is not permissible for you to enter to these programmes or to debate with them if you feel that you are unable to respond to their misconceptions and immoralities, and prove to them that Islam is the truth. Allaah Says (what means): {And it has already come down to you in the Book [i.e. the Quran] that when you hear the verses of Allaah [recited] they are denied [by them] and ridiculed; so do not sit with them until they enter into another conversation. Indeed, you would then be like them.}[Quran 4:140]. So, if you enter to their site and enter into a debate with them while not being able to establish the evidence against them and defend the religion of Islam, then you caused harm to yourself and to your religion. The Prophet 
said: "A believer should not humiliate himself.” The companions 
asked: “How would a believer humiliate himself?” He said: “By exposing himself to what he is not able to deal with." [At-Tirmithi] It could be that you do not know that the evidences of the Christians are weaker than the web of a spider. Indeed, Shaykh Ahmad Deedat
debated with their senior priests and popes in well-known debates and disgraced them in front of the public; these debates are published and recorded on tapes.
Thus, if you are able to debate using good words and in a soft manner then you are obliged to be equipped with knowledge, especially religious knowledge and you should have enough knowledge about their religion, otherwise it would not be permissible for you to enter with them in this debate.
Allaah Knows best.