Boy, I know what this one is about. I have fallen into this trap repeatedly. Maybe it's because I grew up in a pastor's family and constant unquestioned service - filling whatever roles weren't already filled - was a way of life. I still tend to see a ministry opportunity or need and ask myself, "Could I possibly do that?" rather than "Should I do that?" or "Am I the best person to do that?" or "Does God want me to do that?" or "Has God gifted me to do that?"
That question - "Could I possibly do that?" - almost always leads to "Yes" and to a bad experience.
Like the time when I volunteered - out of guilt - to serve as cook for a high school retreat when I was 8 months pregnant. Could I possibly do that? Yes. Should I have done it? No. I don't possess any of the gifts needed for effectively serving in that role: hospitality, service, preparing food, making kind-hearted conversation with surly teenagers while my hormonal condition made me want to smack them, spending two sleepless and painful nights sleeping on the floor while my nearly-born youngster kicked my ribs and stomped on my bladder. No, I don't have those gifts. Bad experience.
What freedom God provides in reminding us that he created us intentionally and with purpose. He doesn't expect us to be anyone else or to minister out of a sense of guilt of shame. There is no guilt or shame in saying no to an opportunity that might actually distract us from God's purpose for us. After all, chances are the need exists because someone else came up with the idea but didn't fill the spot. That doesn't mean God wants us to do it.
At the same time we're setting ourselves free from guilt, though, we might be tempted to see service as a form of self-indulgence and personal fulfillment. I believe service in God's name should bring joy, but often requires self-sacrifice at the same time. How do we serve according to our gifts, and not out of guilt, but at the same time make the appropriate sacrifices to do what God wants us to do?