This question is similar in nature to another support question which I recently answered.
Did you want to include the user’s password or the password for the protected post itself?
Yes, I would like to include the user’s password. Not a password for a protected post.
The entire site requires log-in, so only the user’s main password is needed.
Thanks for the link about BCC to avoid spam email limits.
My need is usually only emailing one specific user at a time or at most 3 or 4 in one day.
Even though I think it is a bad idea and would never implement it, it technically isn’t possible to include the user’s password in an email because they are hashed in the WordPress database. There isn’t anyway to retrieve a plain text password even if one wanted to.