PHONE SYSTEM COMMANDMENTS

Thou shalt use stong surge protection on the AC power and on every phone line!
Thou shalt put passwords on every voice mailbox.
Thine passwords must be controlled by the company owner or manager, not by unfaithful and potentially rebellious mailbox users.
Thou shalt put a list of passwords in at least 17 places, including the inside of a kitchen cabinet door. If your tent does not have a kitchen cabinet with a door, you can chisel the passwords into a rock which is too heavy to be moved by a human being.
Thou shalt read the list again, and obey these commandments until the end of time, and teach these commandments to every inhabitant of the Earth.

Photo shows Charlton Heston as Moses in "The Ten Commandments" (1956)