STOP THE PRESSES! I WAS WRONG!
Thanks to everyone who pointed it out because I actually never knew this (and can’t believe I never knew this), but, no, the Speaker of the House does NOT have to be a member of the House of Representatives. Every Speaker has been a Member, but it is not a requirement.
I love learning something new, but I hate being wrong, so I’m torn about this. But, it’s such an interesting twist that I’m more excited than bothered about not being correct.