Displaying Teaser Text on Home Page

I am using the membership plugin to restrict access to the posts and content in the blog area, but struggling to find the correct settings to enable the teaser text to be seen on the home page. I do “not” want to require the author to use the “more” tag within the post to hide information. Currently all the posts are displayed on the home page with a title, photo and 12 words of content. I would like to keep this – but if they click – would require a sign in. Right now if I restrict the content categories, it does just what I need it to do … but also will not populate anything to the home page.

Thanks in advance