When i answer religious questions i do so with the hope of adding information to the questioner's storehouse of knowledge. Whether my information changes their beliefs or not is for them to decide.
Another purpose in my answering their question is to cause them to dig deeper within themselves for information with which to challenge my answer. This not only helps them to strengthen their own beliefs but also helps me receive more information about their beliefs and what causes them to function the way they do.
By the tone of your question you appear to be a little insecure with your own beliefs and are afraid to be challenged by non-Christians because you might falter.
Don't be afraid of confrontations with people of other beliefs. You will ultimately be strengthening your own current beliefs or grow into beliefs that are more suitable to you and that time of your life.
Those whom i meet
Those whom i meet, as Friends i greet,
And as a Friend i treat them so;
That when in need, or sadly grieved,
i may help their Spirits grow.
For unto this world, as a shepherd i came,
With a Life that's not my own;
And a purpose plain, that's not for fame,
But to help my friends get home.
So when i hear, upon my ear,
The sounds of troubled Souls;
i can do no less, then to do my best,
To help them toward their goals.
And i know i'll find, with the passage of time,
That i've helped their Spirits grow some;
And though appreciated, thanks aren't awaited,
For my friends are always welcome.