Deuteronomy 6:9

9You shall write them on the 6:9 Heb mezuzoth, which—like tefillin (v 8)—also have special significance in Jewish tradition. The (singular) mezuzah is a piece of parchment on which is written this passage (6:4-9) and 11:13-21. The parchment is encased to protect it, and is attached to the right doorpost. By Jewish law, all rooms where people live or sleep (excluding bathrooms) are required to have mezuzoth on the doorposts.doorposts of your house and on your gates.