He doesn't. Any activity on Facebook you'll receive a notification to the email you use to log into Facebook. This is the default (unless you change this)

Also, there is an option on Facebook to show your email, website, phone, etc to friends, friends of friends, and/or strangers.

You'll have to check your privacy settings on Facebook. Also, try logging off of Facebook and looking at your profile so you'll have an idea what a stranger would see.