Yes! To revert your post back to an old version, simply click the "Show Revisions" link on the bottom of your post. If there were multiple published versions of the post, you will find all versions listed - along with the date, time and IP address from which it was published.
By clicking on the link of a past version, you will be able to view the previously published post. Click the "Revert" button in the upper right-hand corner of the webpage to revert the post back to this version.