Passwords

Okay so my bf and I have each other’s passwords, not because we are controlling of each other but because it brings us comfort knowing that we’re that open with each other... we’ve been like this for years and nothing has ever gone wrong. Recently he changed all of his passwords and even took my thumb print out of his phone.. I haven’t done anything to cause this and all of my passwords are the same so he still has to chance to log into my accounts and whatever. But I don’t? I’m trying to explain this whole “fairness” thing to him and he’s just saying it’s unnecessary. But I’m still giving him the fair option even though he isn’t giving it to me... what should I do or say to him?