How to place HTML tags in content from the_content()?

sorry to mark this as an answer for some reason I can’t comment on this question.

Can you explain more what you mean by “I have a list of posts (with excerpts) being displayed in the page using Short Tags.”? Do you have a list of posts excerpts displayed on the front and some number of short tags in the backend that utilize some plugin?

Without more information I can only point you to the content filter on the WP Codex. You should be able to use that to filter the output before it is sent to the browser.