Is there a way to disable a Messages account via command line? I'd like to stop/start receiving SMS/iMessage via command line, to avoid having to go into system preferences. 

Is there a way I can manipulate settings for Messages to enable/disable an account?
It turns out stopping was more logical than expected:

tell application "Messages"
     repeat with s in services
            set n to name of s
            log out s
     end repeat
end tell


It doesn't seem to work the other way around. I've tried and I've tried, and I can't get no satisfaction.