If I use the remove --purge command does that completely erase the package and the configuration files from my system?
From the apt man page:
Removing a package removes all packaged data, but leaves usually small (modified) user configuration files behind, in case the remove was an accident. Just issuing an installation request for the accidentally removed package will restore its function as before in that case. On the other hand you can get rid of these leftovers by calling purge even on already removed packages. Note that this does not affect any data or configuration stored in your home directory.
So to answer your question, yes.