I am traveling back to Boston from Paris, France, with a connecting flight in Lisbon, Portugal. Will I have to go through security or recheck my bags in Lisbon or just when I arrive in Boston?
According to the Lisbon Airport website, whose connecting flight page can be found here, you do not need to go through a security checkpoint when you arrive in Lisbon, only passport control. The same website suggests contacting your airline to make sure your luggage is automatically sent to your final destination.
My hunch is that if you're on a full-service carrier (likely, TAP, I'm guessing), that they'll forward your baggage for you. That's been my experience in Schengen country to non-Schengen country connections elsewhere in Europe.