Impostor syndrome

I recently read about impostor syndrome and how even a highly skilled surgeon doubted her own abilities and would need to quieten her negative self talk before operating.
When I began a new job years ago I remember one of the managers asking me how it was going on about the third day there. I confessed I wasn't sure I knew what I was doing and she wisely told me 'fake it till you make it'. When I left nine years later, I wondered if I was still doing that as I faced each challenge the job brought.
The biggest feeling of being an impostor comes when I stand up in front of the people at church and speak. I have always been an upfront person. When I was in year 7 and the teacher said he would ask someone to thank the politician who had shown us around parliament house, I knew it would be me and so it was. Off the cuff I made the necessary speech. I have been a teacher and trainer, a tutor, a lecturer and in several roles done a heap of public speaking.
But somehow preaching seems different. (My reluctance to say that I preach probably stems from the past where I was taught that only men preach. I have wrestled with that and the place of women in ministry, and so came to the point where I could stand up in church and talk a bit!)
But when I first had this opportunity I surely felt like an impostor. Who am I to speak for God, to share insights from the teaching of the Bible? Surely faking it isn't the deal here. Then I came to the conclusion that it's really an awesome thing but on the other hand it's a matter of sharing what I know of the One I speak of. Telling friends about my understandings, but also my doubts and the days when I feel I am an impostor even to claim to be a follower of Jesus Christ.
Last Sunday again I was the impostor preaching before the masses (well, before a small congregation, actually)  but I was also the recipient of the message.  2 Cor 3 17-18 reminds us that where the Spirit of the Lord is, there is freedom, and that we all reflect God's glory as we encounter that very glory of God. So not impostors at all.