Some bloggers (and I am one of them) are not too happy with the snippitization of their posts by the most recent crop of themes from Blogger.
Older themes (like this one) render the entire post on the home page or end at your jump break.
But the new responsive themes suck up the first few sentences, strip them of all formatting, hyperlinks, and paragraph breaks, and add a "read more" link that goes to the post's post page, automatically.