As an introvert who continues to struggle with my condition, I found a lot to like in this two-part post from Holly Ordway: an introvert’s perspective on sharing your faith in public. Here are some highlights:
So when I was an atheist, I would have responded very badly indeed to a Cheerful Extrovert for Jesus trying to get me into an Important Conversation for My Soul. The thing is, it wasn’t an atheist-Christian thing, but rather an introvert-extrovert thing… but the fact that I’m reserved means that a Christian stranger trying to drag me into conversation, or to foist tracts onto me that I haven’t asked for, is crossing my personal space in a major way. No matter what the message, Christianity or anything else, the Extrovert Stranger’s attempt to engage with me, a highly reserved introvert, would end up with me developing a serious dislike of whatever the message was.
And
Extrovert Christian + extrovert random stranger = Go for it! Apparently you extrovert types actually like talking to strangers. Wow, that’s weird, but sure, have fun, as long as you’ve picked up on the body-language signals that you are sitting next to someone who actually wants to talk to a stranger.
Extrovert Christian + introvert random stranger = Leave the poor sap alone! You will only inflict misery and cause him or her to be reinforced in the idea that Christians are obnoxious pushy loud irritating horrible people. Why would I want to be like you? If heaven is full of people who won’t let me read my book in peace, why would I want to go there?!?
Introvert Christian + random stranger = Peace. Read your book and don’t worry about it. If you tried to talk to that person, you’d feel awkward and it would show… it would not be a successful conversation, and it’s certainly not worth the amount of distracting stress and churning anxiety that will disrupt your work for the rest of the day. If God really, truly needs you to talk to that person, He will work a minor miracle to circumvent the normal social barriers. Seriously.
Remember that not everyone is an extrovert. If you are more introverted, or more reserved, that is how God made you. You do not need to try to witness like an extrovert. In fact, if you try to witness like an extrovert, you will not only feel horribly awkward and miserable, but you will almost certainly be totally ineffective.
And
Our gifts include talent (in the modern sense, of ability and vocation), time (we all have 24 hours in a day), and energy. Apologetics and evangelism, to be done effectively, must take into account all these things — or else it can easily become an exercise in self-aggrandizement or a response to peer pressure.
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Oddly enough, recognizing my own limits has helped me trust God more: He made me, after all, and He will make use of my work within the limits of my capability.