I'm struggling with this issue of how to respond to "Merry Christmas" as a new Muslim revert myself. I hopped onto Google to look for alternatives to my best concoctions....but have yet to find one that doesnt leave me feeling like I am depreciating my religious values on behalf of someone else's misguided feelings. Here is the best I have come up with:
لَكُمْ دِينُكُمْ وَلِيَ دِينِ
There is really no need for you to convince him of your religion .Islam is not seen in words ,it manifests in action.Its the soul of Islam that is a direct expression of its message ,like the taste of sugar, inexplicable unless you taste it ,the sahaba understood Islam from the behavior of Muhammad ,he was an expression ...
The first thing is that you need to study Aqidah before trying to involve yourself in such questions or answering any non-Muslim/atheists questions.
Second, they will have as many questions more than you imagine, and these questions are asked in a wrong way, because their problem is not with Who created ALLAH or How the world existed..etc, their problem is ...
As'salaam | The source of peace
to you | u'Alykum.
God says in Chapter 87, | translating into English
87:9 So remind, perhaps the reminder will help.
87:10 He who is concerned will remember.
87:11 And he who is wicked will avoid it.
Sounds like the person you are speaking with is uncomfortable with anything outside the "cause" and "...