Critics of Christianity - or any other number of issues - sometimes think that skepticism is the default position toward our claims. Always posing questions and doubt, but never offering support for these. They think skepticism is a safe default position despite an argument offered them.
Many critics of Christianity pose counterarguments and reubuttals of our claims. But some merely pose questions to sow seeds of doubt and think they've done enough to dismiss Christianity. Doubts and questions do not constitute counter-evidence. Christianity and Christians offer a wealth of reasons and arguments of a wide variety to support our convictions and try to persuade others. These cannot simply be dismissed with a shrug of the shoulders and a "what if" question. Some questions are sincere inquiries for more information. I'm talking about mere doubt.
This is a simple matter of epistemology and reason, not unique to Christianity. Any position supported by evidence and arguments should be met by critics with reasons and arguments of their own. If they only respond with skepticism, they've done nothing at all to to negate any of the justification for the other view. At this point, one view has evidence to support it, and the other - and skepticism is a position about a view - has none. The position that has been justified has the rational advantage. The one that hasn't, doesn't.
"What if" questions don't count as evidence. All kinds of things are possible, but they aren't likely or rational to believe. If you have good reasons for Christianity, don't be worried about mere "what if" questions that simply pose possibilities without reasons.
Skepticism isn't rational in the face of sound reasons. Skepticism doesn't automatically trump evidence. Skepticism needs it's own evidence against other evidence.
If a belief under debate is, say, 60% likely because of the arguments in favor of it, then not accepting those arguments and the belief that follows from them needs to be explained at that point.
So Ambassadors, when critics respond to your explanation for why Christianity is true and rational by simply posing a skeptical question or objection, let them explain why the mere possibility of doubt trumps what you've carefully explained. Let them carry the burden of proof for skepticism. Let them persuade you, not just sow seeds of doubt by a shrug of the shoulders.
This is really an application of the Columbo tactic. Why, in the face of all of these reasons, choose to be skeptical? Let them explain for a change. And don't be shaken yourself by mere skepticism.