Introductory message on Posts page

I use wordpress as a website first and as a blog secondary to that. I would like to make a specific page for the Blog section that I can link to (and I figured out how to do that), but I would like to have some introductory text at the top of that page explaining what the blog posts are all about.

I made a template page called “Blog” and used the editor to add some text to it. This worked fine and the text showed up on this page until I went to the “Reading Settings” control and chose this Blog page for where to show “Posts” from the pop up menu. Now it just shows the posts, but my introductory text is missing.

Any ideas on how I can make this work?