As I was walking in to my best friend, and roommates room, I saw this hanging outside her door. This is a “Mezuzah”, a common jewish doorpost. She explained to me that the mezuzah is put on the door facing outwards. It is used to bless the room, and you everytime you walk through the door. It is also used as a symbol of a jewish household, to show certain set of rules, rituals and beliefs. It is also associated with the biblical origin of Deuteronomy “And you shall inscribe them on the doorposts (mezuzot) of our house and on your gates”. It is amazing to think such a small doorpost has so much biblical meaning behind it.