Here's a six-part online Bible study on the Principles of Fundraising from Marc Pitman.
I recommend you look at this, even if you have no interest whatsoever in Bible study, and even if you and/or your organization are not part of any faith community.
This is the world many, many of your donors live in. Most donors to most organizations are active religious participants and take seriously their scriptures. It might open your eyes to the thinking of people who are very important to you.