I am writing to provide an explanation for the gap in my employment history as indicated in my mortgage application. Master the art of writing a winning letter of explanation for your mortgage application with our comprehensive guide.I would suggest a few things to say in the letter. Explain what caused the employment gap, and be honest about it. Mortgage lenders might request a letter of explanation for various red flags that come up in underwriting. Learn how to write one, and download a template. A letter of explanation is a brief document you can use to explain something, like a previous bankruptcy, in your financial or employment history. A letter of explanation can clarify your financial situation and get you one step closer to qualifying for a mortgage. Miami-Dade County FY 2012 Surtax RFA. Category 2 and Category 3.