"But sanctify the Lord God in your hearts: and be ready always to give an answer to every man that asketh you a reason of the hope that is in you in meekness and fear:" (1 Peter 3:15)
Dialogue is vital. No Christian need ever think that a non-believer would not want to hear about our faith, our Savior, our God. A common misconception. This is why we need to be ready to answer everyone—including our brother and sister in Jesus—about "the hope that is you".
A perfect example: a past issue of Esquire magazine profiles a man who saved the lives of everyone in a Joplin, Missouri gas station as the tornado touched down a stone's-throw away. The article also interviews a Pentecostal woman (though it doesn't label her as such, should I?) who cried out "Jesus!" as loud as she could over and over and over as the tornado ravaged everything around her. The writer of the article reports the facts and leaves the reader to decide. Or not. What drew me to the issue wasn't anything on the cover but the cascading sequence of "Jesus" in ever increasing font-size, complete with exclamation points.
Another interesting thing about this article is how it delineates the doctrines of Pentecostalism from an observer's objective viewpoint. It speaks of this woman's beliefs as simply that: what she believes. And it's accepted and respected. Ironically, these very things (the distinct indwelling of the Holy Spirit as something separate from salvation, speaking in tongues, etc.) are viewed with skepticism at best and shunned and silenced at worst in other, more conservative denominations within Christianity.
If the world can talk about it, why can't we? And not just denominational distinctions. Listen as our brother and sister share what God has done in their life, and be "slow to speak" (James 1:19). God is doing something in all of our lives. I believe that all things (including conversation) should be done "decently and in order" (1 Corinthians 14:40), i.e. appropriately.
What God is presently doing in our church (and churches) is going to spill out into the world as it did in Joplin. I have a sneaking suspicion that the author of the article knows a miracle happened that day. And thank God that this woman was willing to share her faith and beliefs without shame. How will we know to answer questions about other denominations, about our faith in general, unless we're willing to share what we believe? And how. And why.
"Let your speech be alway with grace, seasoned with salt, that ye may know how ye ought to answer every man." (Colossians 4:6)