The sermons feature is intended specifically for sermons but there are some things you can do. You can rename the page that uses the Sermons template, widget titles, menu links, etc. from within the WordPress admin area. If you want to change the wording used in the admin area, you could make an English to English translation.
Note that “sermon” is used in each sermon’s URL. This is called the sermon post type rewrite slug and is hard-coded, meaning you would need to modify the Church Content plugin’s post type registration by using a custom plugin. Read Modifying Post Types for more information.