So, you're walking down life's path and then you get to heaven and Jesus will say - what? But, hey, what do you mean heaven? Are you sure that's where we're going to live? How does the new earth come into it? What about the new Jerusalem?
A Jehovah's Witness comes to your door. Can you explain the Trinity? How can the Father, Son, and Holy Spirit be one God? Wouldn't that make it three Gods?
You try to tell a friend about Christ and she says "Yeah, but if there really was a good God who is all powerful why did he let that happen to me when I was a child?" Do you have an answer?
A Mormon says "God was once a man just like us, I mean, look at Jesus - he was a man and yet you say he is God. What's the difference between him and us?" Can you honestly explain that?
Can you really explain how the Holy Spirit inspired the scriptures? Can you show what each writer meant and what his hearers would have understood? And how will you explain how to apply the scripture? And who is this Holy Spirit?
"Hey, I'm not so bad over all. Why would God punish me forever?" -- Well?
What does the Bible mean when it says the blood of Jesus saves us? Is it the real blood? How could it all go around?
Why did Jesus have to die - couldn't he just forgive us without all that?
How can we have both a spirit and a body? Can we live without a body? What will our new bodies look like?
A friend is worried that he just doesn't do enough for people around the world, but you know he gives a lot of money to relief agencies. Can you show him the Biblical difference between conviction and guilt?
What sacrifice is okay to achieve unity in the church? How much should we put into living like a Christian? How absolute are what truths?
What are angels for? Where did Satan come from? What are they made of?
Do we have to live by the Old Testament rules? If so, which ones? Why are there still Jews?
"All religions really point to the same truth/god. It doesn't matter what you believe as long as you are sincere." Can you explain why that is not true?
To what do we have to look forward? Will we really be sitting on clouds playing harps forever?