In the book of Exodus, the word Mezuzah occurs for the first time and is understood to mean “doorpost.” The origin of the word is unclear although there are claims that it originates from an Assyrian word, “manzazu.” In ancient times Israel was held captive by Pharaoh. Rabbi Moses communicated with Hashem and came to understand plagues would come upon the Pharaonic household of Egypt for holding Israel unto slavery. Moses called down 7 plagues upon Egypt. Moses instructed the Jewish households to write upon the doorposts in lambs blood the name of Hashem to protect the Jewish household from the angel of death as it passes over Egypt. The Mezuzah is the scroll of parchment affixed to the right-hand doorposts of Jewish homes. More often than not the parchment will be protected by an attractive case. The scroll has two sections from the Torah written upon it. Both sections are from the book of Deuteronomy, one is part of the sixth chapter, one part of the eleventh. It contains a part of Jewish daily prayers known as Shema. In the passage, among other things, Hashem commands the Jewish people to heed his words, to love Him and to be constantly aware of him. In the passage there is a reference to writing of “these words” on one’s doorposts. On the back of the scroll is written one of the names of Hashem, Sha-dai which is also an acronym for the Hebrew words that mean “Guardian of the Doors of Israel" The Mezuzah protects all those that reside in a household by a guardian in the spiritual world. That is the intention.