chmod is one of a family of commands in the Unix computer operating system that is used to give permissions for who can access  the system.  What can be read and who can read it.  What can be written to and who can write.  What groups are allowed, and not.  When to allow and when to deny access.  Who has the power to execute and who does not.  Who owns and who is disowned.  

These controls are a pretty good set of metaphors for reading and interpreting the scripture of the Bible.  Like chmod, the Revised Common Lectionary is, so to speak, a system command of permissons and selections.  But the texts themselves have a way of trespassing all prescribed usages.   Nor is there any exclusive content that can be absolutely set apart as some inviolate, static, Word.  The very marks on the page cause us to reset the access codes.  The Word has a life of its own, and we are all implicated in that life.