"You shall write them on the doorposts [in Hebrew, "mezuzoth"] of your house" (Deut. 6:9).
The Jewish mezuzah refers to a parchment bearing the words of Deuteronomy 6:4-9 and 11:13-21 and rolled up in a case or tube that is attached to the doorpost of the house and other rooms. It is affixed diagonally, owing to the fact that authorities disagreed on whether to place it horizontally or vertically. So they compromised!
The doorpost of your house signifies the dividing line between the goings on of the world and the sanctuary of the home. God means to make of your home a little heaven on earth. A place of faith, hope, and love in the midst of trying times.
How so? His Word. Luther wrote the Small Catechism as a way to fill the home with the blessing of the Ten Commandments, Creed, Lord's Prayer, Sacraments, Prayers, and an understanding of our Duties.
Reclaim your home as a place of peace. Guard against strangers and "strange teachings" (Heb. 13:9) entering your home through the television and computer. Make certain a cross or crucifix occupies a central location. Invite the pastor over to give a house blessing.
And petition God to make your home your little heaven!