Moses Tells the People to (as It Were) Place Passages of Scripture between Their Eyes, on Their Hands, on the Posts of Their Houses, and on Their Gates as Constant Reminders of Their Covenants with the Lord
18 Therefore shall ye lay up these my words in your heart and in your soul, and bind them for a sign upon your hand, that they may be as frontlets between your eyes.
19 And ye shall teach them your children, speaking of them when thou sittest in thine house, and when thou walkest by the way, when thou liest down, and when thou risest up.
20 And thou shalt write them upon the door posts of thine house, and upon thy gates:
21 That your days may be multiplied, and the days of your children, in the land which the Lord sware unto your fathers to give them, as the days of heaven upon the earth.
Elder Bruce R. McConkie wrote:
“Devout [Jewish] fathers wore phylacteries during prayer (the Pharisees wore them all day long), and these contained parchments whereon were written these four passages from the scriptures: Exodus 13:1–10, Exodus 13:11–16, Deuteronomy 6:4–9, and Deuteronomy 11:13–21. On the doorpost of the home of every devout Jew hung the Mezuzah, which contained a parchment whereon was written, in twenty-two lines, Deuteronomy 6:4–9 and 11:13–21, as both of these passages command. The Shema, composed of Deuteronomy 6:4–9, Deuteronomy 11:13–21, and Numbers 15:37–41, was repeated twice each day by every male. Family prayers were the order of the day in all homes.”
(The Mortal Messiah: From Bethlehem to Calvary, 4 vols. [1979–81], 1:224.)