Not wishing to screw up the interview for my first paid job in the voluntary sector, I spared him further details of my intention to make a strategic contribution to the charity's development.
And I suppose he had a point. As finance director, it would indeed be my responsibility to ensure the integrity of the financial reporting system.
In a small charity, where the finance department was made up of just one person - me - that was going to involve having my sleeves rolled up a lot of the time.
So it's with one eyebrow raised that I listen to the regular exhortations of the Charity Finance Directors' Group for finance professionals to assert their strategic role at the heart of the senior management team.
Of course, the finance director should be right there, and, indeed, most will want to be - who wouldn't rather work on business planning than on the bank reconciliation?
But it's hard to think strategically with the auditors at the door.
Instead of making the hands-on finance person feel like a bit of a drip for spending too much time in the back office, perhaps we could think more about why it is that in so many organisations a valuable resource is being underused.
Many organisations genuinely cannot justify employing a full-time finance director. What they really need is someone who is also capable of being a financial controller and a book-keeper from time to time as the job demands.
It may seem like a waste of resources to pay somebody with the calibre of a finance director to input data into Sage, but it is often easier, cheaper and more cost-effective than hiring two part-timers and a consultant.
Greater obstacles are to be found in the attitudes of many trustees.
I'm afraid there are still plenty of boards that think the chief executive is the only one they need to bother about - a view not always challenged by the chief executive. The rest of us are simply known as his or her team.
Attitudes are changing, and that's because, even in small organisations, finance directors are finding opportunities to show, not just say, that they are ideally placed to work at a strategic level.
But don't be ashamed if you still know where the petty cash tin is.
- Heather Lamont is head of charity business development at HSBC Investments.